Printer, printing control apparatus and printing system using unique job identifiers, and control method therefor

ABSTRACT

When a command for the status response is issued from a host computer to a printer, a data-receipt administration portion adds, to the received command, an ID peculiar to each command, and stores the commands and the peculiar ID; and a data-transmission administration portion immediately returns the ID added to the command to the host computer. A printer-language analyzing portion analyzes the received command, while a status-response processing portion produces information that must be responded to the command. The produced response information is, together with the previously-stored ID added to the corresponding command, returned from the data-transmission administration portion to the host computer. The host computer collates the previous-received ID and the ID received together with the response information with each other so that the command and the corresponding response can be made correspond to each other.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a printer apparatus and a controlmethod therefore in which data received from, for example, a hostcomputer, is analyzed so that an output process is performed.

2. Related Background Art

In a conventional printer apparatus characters, graphics and/or imagesare formed in accordance with a command issued from a host computer soas to output a document or to control the printer apparatus, such asprinter initialization.

Another conventional printer apparatus has a function for responding toa host computer through a bidirectional interface in accordance with acommand transmitted from a host computer. The response providesinformation indicating the state of the printer apparatus, the setenvironment of the printer apparatus, the progress of the documentoutput and font to be used.

The foregoing function for transmitting various information items aboutthe printer apparatus to the host computer is called, for example, a“status response”.

A variety of bidirectional interfaces have been used in the statusresponse, as exemplified by a known RS-232C, Bi-Centronics, Ethernet andthe like, developed recently.

In recent printer apparatuses, any of the foregoing bidirectionalinterfaces have been employed as a standard interface in place of theconventional mono-directional interface.

It is considered that a printer system performing the status response bymeans of the foregoing bidirectional interface will be widely used.

Use of the status response function will enable the host computer torecognize the state of the connected printer.

For example, a status response indicating whether or not the printerapparatus is able to print out data at present, or information supplyindicating occurrence of a problem, such as wanting of paper or paperjamming, will eliminate a necessity for a user to go to the position atwhich the printer apparatus is located, to confirm the state of theprinter apparatus, even if the printer apparatus is located remotelyfrom the host computer.

If information about fonts which can be used with the printer apparatus,about type of graphics which can be formed, and about the printerlanguages which can be executed, is status-responded, the informationserves as instructions to use a proper font and to form an image byusing a printer language when document data to be output is processed.

With the conventional mono directional-interface printer apparatus, thehost computer cannot recognize whether or not the printer apparatus hascorrectly formed an image and whether or not the printing operation isstopped due to a problem after the host computer has transmitted data tothe printer apparatus. When data is processed, the host computer mustprocess image data to be formed on an assumption of the fonts andimage-forming functions of the printer apparatus. Therefore, it isconsidered that a system, using both a bidirectional interface and thestatus response function and causing the host computer to acquireinformation of the printer apparatus to perform administration, will beusually used.

In a case where the status response is performed by using thebidirectional interface, a command for the status response is issuedfrom the host computer to the printer apparatus.

The printer apparatus analyzes the language in the command to recognizethat the command orders a status response, followed by examininginformation about the subject printer apparatus. Obtained information isdescribed in a format of data to be transferred, and the information istransmitted to the host computer.

The host computer receives the information, and analyzes data so as torecognize the state of the printer apparatus.

As described above, the interface between the host computer and theprinter apparatus is established in two directions, one of which runsfrom the host computer to the printer apparatus, and another of whichruns from the printer apparatus to the host computer.

The foregoing two-directional data communication is performed by amethod determined depending upon the method of the bidirectionalcommunication. For example, a method is employed in which transmissionand reception are performed at individual timings, or a method isemployed in which either of the transmission or the reception can beperformed at a time, and switching is performed between transmission andreception as the need arises.

In the printer apparatus, a major portion of the data communication isshared by transmission of data from the host computer to the printerapparatus.

Therefore, greater importance is placed on data transference from thehost computer to the printer apparatus than transference from theprinter apparatus to the host computer, and the data flow is intended tobe performed efficiently by adjusting the algorithm of the interface andthe hardware.

As a result transmission and reception are not always performed at thesame timing. For example, in a case where output data including a statusresponse has been transmitted, the structure, in which the outputprocess is given priority, sometimes inhibits return of the statusresponse until the output data is processed to a certain extent. Toperform the response, receipt of the output data must be temporarilystopped, or a portion of the performance of the CPU must be used toperform the response operation. As a result, an efficient printingprocess cannot be performed.

The transmitting and receiving portion of the host computer has asimilar problem.

Generally, the process for the host computer to receive a response fromthe printer apparatus has lower priority than that given to the processfor transmitting output data. Also the transference rate of theoperation of receiving data from the printer is usually lower than thatof the operation of transmitting data to the printer.

As described above, the usual printer apparatuses focus on data transferfrom the host computer to the printer apparatus, and the response isgiven low priority. Therefore, even if a command for the status responseis issued, its response is not always returned immediately.

To prevent delay due to the difference in the processing speed andprocessing timing among the host computer, the interface fortransmitting/receiving data and the printer apparatus, a data buffer isgenerally disposed at each contact.

For example, a data buffer, called a “receiving buffer” is provided toadjust data transference from the host computer to the printer apparatusthrough the interface, the receiving buffer being disposed at the inletport of the printer apparatus. Data transmitted through the interface istemporarily stored in the foregoing buffer. Since the foregoing storageprocess is performed in synchronization with the processing speed andthe processing timing for the interface, load on the interface can bereduced, and thus the process can be performed under the most propercondition for the interface.

Also the printer apparatus is able to receive data from the receivingbuffer at the processing-speed and processing timing thereof. Thus, theprinter apparatus is able to perform the process thereof under the mostproper condition.

However, the temporal storage of data inhibits immediately processing ofdata transmitted from the host computer, but causes a somewhat long timeto take place before start of the process.

Even if the host computer issues a command for the status response,command data is temporarily stored in the receiving buffer or the like,and then the printer apparatus sequentially reads the buffers. When theprinter apparatus receives the command data, the process is started.

Therefore, the presence of a buffer of the foregoing type in a dataconveyance passage will cause a certain time to be taken from the issueof the command for the status response to the receipt of the response.

A status response process to be performed in the printer apparatus willnow be described.

It sometimes takes a long time to take information of a responsedepending upon the contents of the response. An assumption is made thata command for the status response is issued to take information of allcharacters of included fonts by searching the all characters. Theforegoing process sometimes takes several seconds though the perioddepends upon the state of the included fonts.

An assumption is made that a command for the status response has beenissued with which if the state of the printer apparatus is changed, thenthe change is communicated to the host computer.

For example, a command for the status response is, during a documentoutput, issued with which if all pages have been completely output, thenthe output must be communicated to the host computer.

In the foregoing case, a time difference of tens of seconds to severalminutes sometimes takes place from issue of the command for the statusresponse to completion of discharge of all pages and return of theresponse.

Since the transmission of output data from the host computer cannot bestopped even if the response is not returned, the timing of the commandfor the status response and that of the status response are completelyshifted.

As described above, the status response is not always returnedimmediately after the host computer has issued the command for thestatus response.

The status response is sometimes returned immediately, while the same isreturned after several seconds to several minutes or longer. Therefore,the host computer must wait for the return, followed by analyzing thecontents of the return to recognize the state of the printer.

In a case of the conventional printer apparatus which does not use thestatus response frequently, a somewhat time delay can be allowed in theprinting system.

However, information interchange to and from the printer apparatus usingthe status response will be performed frequently and widely used.

The shift of the timing between the transmission and the response causesa critical problem to arise. An assumption is made that a printer systemis present in which a printer apparatus is required to transmit avariety of status responses. FIG. 7 is a zigzag chart showing exchangeof messages between the host computer and the printer of a system of theforegoing type. A portion of statuses takes a long time to checkcorresponding information or a portion of the same is not returned if acertain state of the printer is not changed, depending upon the type ofthe statuses.

Referring to FIG. 7, an assumption is made here that the host computerissues, in document output data, the following three commands for statusresponse to the printer in the sequential order below: (1) “notifydischarge of the page, which is being printed”, (2) “send informationabout the number of fonts among the fonts included in the printerapparatus that are larger than 12 points”, and (3) send informationwhether or not the printer apparatus is able to receive data at present.The printer apparatus sequentially analyzes the supplied commands toperform corresponding status responses, output of the document andcontrol of the printer apparatus.

Although the status response with respect to the command (1) is intendedto be performed in the foregoing sequential order, the response cannotbe performed immediately because the page is being printed out.

As a result, performing of the foregoing response is caused to wait forthe completion of the page discharge. Since the processing efficiency isunsatisfactory if all processes are stopped in the foregoing waitingstate, the operation proceeds to a next command process.

In order to return the status response with respect to the command (2),fonts in a large data volume included in the printer apparatus must beretrieved to search the font meeting the specified conditions. Theforegoing retrieval takes a certainly long time, though the time dependsupon the quantity of the fonts. If other processes are stopped toperform the foregoing retrieval process, the processing efficiencydeteriorates.

In a case of a system capable of performing a parallel process, a nextcommand process can be performed during the retrieval process.

Then, a status response with respect to the command (3) is performed.The foregoing status required to be responded is a simple status thatinquires whether or not the printer apparatus is able to receive data.Therefore, the response can immediately be performed. Since the contentsof the response are used to discriminate that data can immediately betransmitted at present, it becomes useless if it is not returnedimmediately.

The printer apparatus immediately returns the response with respect tothe command (3) to the host computer (process (3′)).

After a certain time has passed, the font retrieval required in thecommand (2) is completed. Then, the status response with respect to thecommand (2) is returned to the host computer (process (2′)).

After a certain time has passed, the page discharge is completed, and astatus response with respect to the command (1) is returned (process(1′)).

As described above, the sequential order and timing at which the statusresponses are returned from the printer apparatus are not always thesame as the sequential order and timing at which the host computer hasissued the commands for status response. Therefore, the host computermust discriminate to what command the returned response relates.

If simple responses “OK” and “34” are received, it is difficult torecognize the commands to which the foregoing responses correspond.

To overcome the foregoing problem, a conventional discrimination methodhas been known, in which information in the form of a character stringor the like indicating the command to which the response corresponds isadded to the status response to be returned.

For example, the status response with respect to a command (3) inquiringwhether or not the printer apparatus is able to receive data is formedinto a form “STATUS ONLINE=OK”.

As a result, discrimination can be performed that the state “ONLINE”,which is whether or not the printer status is in a state where data canbe received, is permitted, that is, “OK”.

Since added information in the form of an individual character string isassigned to each content of the response, the host computer is able todetect the command, to which the returned response corresponds bysimultaneously discriminating the foregoing character string.

Also in a case where any of the status responses is received, addedinformation indicating the contents enables the command, to which theresponse corresponds, to be detected even if the sequential order andthe timing of the return are out of order.

However, unsolved problems remain.

Although the foregoing method enables the status responses for differentitems to be identified, a problem arises in a case where the same statusresponse for the same item is repeatedly demanded, a problem arises indetermining to what command for the status response the returnedresponse corresponds.

Although to what item the response corresponds is described in thereturned information in the form of the character string or the like, inthe case where the status responses relate to the same item, a furtherdiscrimination cannot be performed because the information foridentifying the item is the same.

An assumption is made here that the host computer intends to registerfont data into a printer apparatus. FIG. 8 shows an example of messagecommunication between the host computer and the printer in the foregoingcase. Referring to FIG. 8, the host computer instructs a storage unit inthe printer to perform a preparation operation, such as securing aregion for registering font data, which will be then performed, and toperform an initialization operation (process (1)).

In accordance with the foregoing command, the printer apparatus causesthe storage unit to perform the preparation process. After it has beencompleted, the printer apparatus returns status response “STATUSFONT-DOWNLOAD=OK” to the host computer so that completion of thepreparation is communicated (process (2)). In accordance with theforegoing information, the host computer starts registering font datainto the printer apparatus (process (3)). However, it is possible thatthe status response (2) does not correspond to font registrationdeclaration in command (1), but is a response to another fontregistration declaration command (4) issued in another process or thelike.

Even if the correct status response indicating completion of thepreparation of font registration corresponding to the command (1) is thestatus response (5), which will be then returned, they are the statusresponses relating to the same item, causing information expressed by acharacter string or the like to be made the same. Therefore, the twostatus responses cannot be distinguished.

Although the preparation has not been completed, registration of fontsinto different storage regions fails. Also a previous registrationintended in another process fails.

In recent years, a system has been used widely in which one printerapparatus is simultaneously used by a plurality of host computers,processes and users.

In an environment of the foregoing type, disorder of the foregoing typetakes place frequently.

Even if the two timings are the same, disorder of the sequential orderof the returns of the status responses and the timing of the commandsfor status response prevents smooth information exchange between thehost computer and the printer apparatus using complicated statusresponses. In this case, constitution of an advanced printer system, inwhich the control of a host computer and that of a printer areintegrated, encounters a problem.

The operation of an output of a document will now be describedspecifically.

In a case where one document is printed, output data transmitted from ahost computer or the like to the printer apparatus is usually formed asshown in FIG. 25. A set of output data is called a “job”.

Initially, start of data output job is declared (process (1)), withwhich supply of output data to the printer apparatus is notified.

Then, the environment of the printer is initialized (process (2)). Thereis a possibility that the environment of the printer has been changedvariously due to data supplied previously. If new data is processed inthe foregoing state, the process is sometimes undesirably affected bythe changed environment, and a desired printing operation cannotsometimes be performed. Therefore, the environment of the printer isinitialized prior to starting the output process so that the influenceof the previous process is eliminated.

Then, the environment of the printer for use in the output operationwhich will now be started is set (process (3)). For example, the size ofpaper to be printed out is set, and the font for use in the printingoperation is downloaded from the host computer to be registered. Theforegoing previous preparation enables an ensuing printing process to beperformed correctly.

A sequence of the processes (1) to (3) are collectively called aprevious process of the job.

Then, a printing out process is performed (process (4)). Data output isusually performed in such a manner that data for forming images ofcharacters, graphics or images is described, after data for one page hasbeen described, a discharge command is issued. By repeating theforegoing process for the pages to be output, a document consisting of aplurality of pages can be printed.

After instruction to print all pages has been completed, a post processis performed such that the environment of the used printer is restored(process (5)) in such a manner that the changed environment of theprinter is restored, and the used font, which has been registered, isdeleted. Thus, the environment is arranged for another output, data ofwhich will be supplied later.

Finally, job completion of the output data is declared (process (6)). Asa result, the printer apparatus recognizes completion of one dataprocess.

A sequence of the processes (5) and (6) are collectively called a postprocess for the job.

The foregoing process is a general example, and there sometimes arecases where the respective processes cannot clearly be divided becauseof somewhat complexity. For example, the initialization in process (2)is undesirably and automatically performed simultaneously with the startdeclaration in process (1), or the post process in process (5) isomitted. However, it can be considered that the process is schematicallyconstituted as described above.

A sequence of processes (1) to (6) is generally called a “job” (or a“printing job”). When one document is output from the host computer, theprinter apparatus usually processes data in the job units. By receivingthe job start declaration (1) and other previous processes, theenvironment for performing the printing job is arranged, and then theprinter apparatus starts the job process. By receiving the jobcompletion declaration (6) and the post processes, the subject job iscompleted, followed by receiving a next job.

In a case where a plurality of jobs are output from the host computer, aplurality of jobs corresponding to the document output are sequentiallytransmitted. The printer apparatus sequentially processes and prints outthe supplied plural jobs in job units.

Also in a case of a network or the like where a plurality of computersare connected and a plurality of users respectively perform documentoutputs, the printer apparatus sequentially processes, in job units, andprints out the plural jobs supplied from respective data sources.

As described above, the foregoing printer system, in job units,processes the outputs from a plurality of host computers, users, anddocuments so that disorder is prevented.

Then, status response process in each stage of the job will now bedescribed.

In a stage (process (3)) of setting the environment of the printer shownin FIG. 7, information, such as the present environment items for theprinter and set values that can be set to the items must be recognizedto set the environment of the printer.

In an example case where printing is performed on large-size paper, datato be described becomes considerably different depending upon whetherthe maximum paper size for the printer is A3 size or B4 size. It isprobable that the size is different depending upon the type and versionof the printer. Also it is probable that the printer is adapted to onlyB4 size or smaller. Even if the printer is adaptable to the A3 size, theloaded unit, such as a paper cassette, sometimes inhibits the printingoperation with A3 paper.

The type of fonts included in the printer apparatus is also importantinformation to describe a document. In an example case where charactershaving a size of 72 points are intended to be printed, correct printingcannot be performed if the foregoing font is not included in theprinter. Depending on the situation, required fonts must be downloadedfrom the host computer so as to be registered into the printer.

If the printer apparatus has a function of receiving compressed data,image data or the like, the quantity of which is large, can betransmitted while compressing data, and therefore time required totransfer data can be shortened significantly. If the foregoingconvenient function is provided, the host computer takes an excessivelylong time to perform the process if it does not know the function.

Since, for example, the contents of the description of output data arefrequently changed due to the state of the printer apparatus, the stateof the printer must be investigated. In order to investigate the state,a status response is used. The status response enables all informationof the printer apparatus, such as the size of paper and the type of thefont, that can be used, and the empty capacity of the RAM, to beobtained. By recognizing the state and the performance of the printer,output data can be described in the most proper form, and thus theperformance of the printer can be attained.

In a stage of, for example, output of each page (process (4)), the stateof the printer, which is always changed as time passes, is transmittedto the host computer by means of the status response.

If paper runs out during output, a status response “STATUS PAPER-OUT”,indicating running out of paper, is transmitted to the host computer. Inresponse to the status response, the host computer displays an alarm ofpaper out for a user on a screen of a computer or the like. If printingcould not be performed correctly due to any problem, a status responserequiring again transmitting data is sent in order to again perform theprinting operation. Even if the printing operation is being performed,intermediate state, for example, the page to which printing has beenprogressed, is notified.

By transmitting information, such as the environment and performance ofthe printer and state of the same, that is always changed as the timepasses, the host computer is enabled to recognize the state of theprinter.

While understanding the concept of the job and example use of the statusresponse, problems experienced with the conventional printer apparatuswill now be described. An example case will now be described about astatus response used when a job for outputting a plurality of documentsis 20 performed (see FIG. 26).

Initially, the operation in the host computer will now be described. Anassumption is made here that a host computer or the like intends tooutput a plurality of output jobs from the printer apparatus. In a casewhere a plurality of documents are output, the host computersequentially processes the document output processes.

Initially, the first document is output. Start of the job is declaredwith respect to the printer, the environment of the printer isinitialized, and a previous process, for example, setting of theenvironment of the printer, is performed to output document (process(1)).

Then, the host computer reads the contents of the document, to beoutput, from a document file or the like to judge a proper layout of thecharacters, graphics and images in accordance with the read contents,followed by converting the contents of the image to be formed into aprinter language description format. Then, the converted contents are,as output data, transmitted to the printer apparatus (process (2)).

After output data for all pages has been transferred, the host computerrestores the environment of the printer, and performs the post process,such as declaration of the job completion (process (3)). Thus, theoutput of the first document, that is, Job 1, has been completed for thehost computer.

Then, the host computer starts output of a next document, that is, Job 2(process (4)). Also the Job 2 is performed similarly to the Job 1. Ifthe document output is continued, Job 3 and Job 4 are performedsimilarly.

Then, process to be performed by the printer apparatus will now bedescribed.

When data of the previous process (1) has been received from the hostcomputer, the environment of the printer is initialized, and therequired environment is set (process (1′)).

At this time, information about the size of paper, that can be used, andinformation about the empty memory capacity in the printer are notifiedto the host computer by the foregoing status responses. In accordancewith the foregoing information, the host computer adjusts output data tocause a most proper printing process to be performed.

Since the foregoing status response is usually immediately returned fromthe printer apparatus when the host computer requires, the process (1)for the host computer and the process (1′) for the printer apparatus aremade substantially synchronous.

Then, output data in process (2) is received from the host computer. Theprinter apparatus analyzes the supplied output data to form images ofcharacters, graphics or images. Then, a page break command is received,and paper, on which the image has been formed, is discharged (process(2′)).

At this time, the foregoing status response causes information about thepage which has been discharged and that about the state of the printer,such as shortage of paper, to be transmitted to the host computerwhenever one page is discharged. The host computer receives theinformation so as to recognize the state of the printer apparatus.

However, the output process to be performed by the printer apparatustakes a certainly long time because a long time takes to developcharacters and graphics or the output speed for the printer engine islimited. Accordingly, there is sometimes a case where the host computerhas completed the output data processing process (process (2)) and theprocess for transferring data to the printer, but the printer apparatusis performing the image forming and developing process (process (2′))and the page output process.

As compared with the data processing and transfer process in the hostcomputer that are usually completed in several seconds, the imageforming and output process in the printer apparatus takes tens ofseconds in a shortest case, and sometimes takes several minutes in aslowest case.

Recently, to overcome the difference in the processing speed, alarge-capacity receiving buffer is provided for the printer apparatus toforcibly store data transmitted from the host computer in order to makethe host computer quickly free from the printing process. Therefore, theprocess to be performed by the host computer is completed furtherquickly, thus causing the difference in the processing speed from thatof the printer apparatus to be made considerable.

As described above, in the image forming and output process, the process(2) for the host computer and the process (2′) for the printer apparatususually are not performed at the same timing. In the foregoing stage,the process in the printer apparatus tends to be delayed.

The delay taken place in the printer apparatus causes the command of thepost process (process (3)) commanded by the host computer not to beprocessed immediately, but the command is temporarily stored in thereceiving buffer. After the image forming and output process (process(2′) for the printer apparatus has been completed, the post process isperformed (process (3′)).

Also output data of a next job (process (4)) in the host computer isusually and temporarily stored in the receiving buffer, but is notimmediately processed by the printer apparatus. The foregoing process isperformed after the previous job has been completed.

Therefore, a state is frequently realized where although the hostcomputer is performing a next job, the printer apparatus is outputtingthe previous job. The delay of the process timing between the hostcomputer and the printer apparatus raises a critical problem in thestatus response.

An assumption is made here that when the host computer is performing theoutput data processing and transferring process in Job 2, the printerapparatus is in the image forming and output process in Job 1.

The printer apparatus transmits, to the host computer, information, suchas “discharge of the third page has been completed” as status responsewhenever one page is discharged. This means “discharge of the thirdpage” in the “Job 3”. In the conventional status response, onlyinformation “the present page” has been returned. Therefore, there is apossibility that the host computer erroneously recognizes such that theforegoing process is “the third page” in the “Job 2”, which is beingprocessed by the host computer.

When the information about the type of the registered fonts required inthe Job 2 is responded by the printer apparatus for example, the hostcomputer has already processed the Job 3. Thus, there is a risk thatdisorder takes place in any status response, as well the page dischargestate.

Recently, an environment, in which one printer apparatus is commonlyused by a plurality of host computers, processes and users, has beenwidely employed. In the foregoing environment, disorder of the foregoingtype takes place frequently.

Even if the two timings are the same, disorder of the timing of thecommands for status response and the returns of the status responses ina plurality of jobs inhibits information exchange between the hostcomputer and the printer apparatus using complicated status responses.In this case, constitution of an advanced printer system, in which thecontrol of a host computer and that of a printer are integrated,encounters a problem.

As described above, the conventional printer apparatus has no means foridentifying the job in which a status response is made when the statusresponse is transmitted to the host computer. Therefore, disorder takesplace in the host computer, and thus the host computer cannot easilyrecognize the state of the printer.

In a contrary case where a plurality of jobs are sequentially processedas described above, a problem rises in the job process if each job datais not prepared in a correct job format. Thus, critical disorder takesplace in the overall printing process.

A case will now be considered in which a job for outputting a pluralityof documents is processed as follows (see FIG. 42).

An assumption is made here that document data of three jobs, Job 1, Job2 and Job 3, has been transmitted from the host computer or the like.The printer apparatus sequentially receives the job data to one by oneanalyze their contents to perform corresponding document outputprocesses (process (1)).

The foregoing job data is arranged to be described in the foregoing jobformat. The printer apparatus analyzes the job data in accordance withthe foregoing description rule.

If data has been interrupted during the Job 1 for example (process (2)).

Although the printer apparatus continues its process to the point of theinterruption, the printer apparatus cannot determine the ensuingprocess.

The foregoing interruption of job data takes place due to variousreasons.

For example, the following cases can be considered: the performance ofthe interface, which is performing data transfer, causes the supply ofensuing data to take a long time; the printer apparatus is busy inperforming operations and therefore data receipt is temporarily stopped;and the processing speed in the host computer is too slow to processdata in time.

The foregoing problems are basically overcome due to a time lapse. Wheneach problem is overcome, ensuing job data is again transmitted.

Other cases can be considered that a communication line is disconnected,and therefore job data cannot be transmitted; a problem arises in thehost computer, and thus processing of job data is stopped; and the hostcomputer disregards the job data format and ends the job process withoutformal job completion declaration.

The foregoing factors are not usual cases but are caused from specialreasons, such as accidents. Therefore, the foregoing problems cannot beovercome even if the time passes, and the job process cannot be againperformed.

If interruption of job data takes place, the printer apparatus waits forsupply of job data from the host computer (process (3)).

If data supply delays occurring due to the low performance of theinterface, the delay can usually be overcome in several seconds.

If ensuing job data is transmitted after a certain time, it is analyzedand processed. Thus, a document can be output without problem.

However, in the case where processing of job data has been stopped inthe host computer, no ensuing job data is supplied thought it is waitedfor.

However, the printer apparatus continuously waits for the supply of jobdata because it cannot discriminate the reason why the job data has beeninterrupted.

Since the printing process in Job 1 is being performed in the waitingperiod, next Job 2 and Job 3 cannot be performed (process (4)).

That is, all job processes are stopped in the foregoing state, and awaiting state is realized.

Thus, smooth operation is prevented, and the efficiency deteriorates.

Accordingly, a means called “job time out” has been employed.

In the job time out process, time taken from the moment the job data hasbeen interrupted is measured.

Even if following job data is not supplied after a predetermined timehas passed, a discrimination is performed that the job cannot becontinued due to a problem, followed by forcibly stopping the job(process (5)).

By performing the job time out process, the interrupted Job 1 is endedhere, followed by starting the Job 2 and Job 3 (process (6)).

That is, the Job 1, that is considered impossible to be again performed,is abandoned, and its process is stopped so as to make effective theensuing Job 1 and Job 2.

Thus, in a printer apparatus in which a plurality of job data items areprocessed, even if a partial problem takes place in a job, all offollowing jobs are not stopped, but the partial job encountered theproblem is omitted, and other jobs can be performed.

Note that the lapse time for use in the discrimination in the job timeout process must be proper length.

If the time is too short, the job is ended even in a case where thedelay takes place due to the performance of the interface, and even jobdata, that can be correctly output, can be canceled.

If the time is too long, a long time takes to wait for the supply,causing the printing efficiency to deteriorate.

The length of the discrimination period must be determined considerablyprecisely because it depends upon the performances of the printerapparatus, host computer, and the interface.

To properly set the time, considerably sufficient experience andknowledge are required and it is usually determined to a relativelyproper value.

Since interruption of job data takes place under a variety ofconditions, it is impossible to determine the perfectly properdiscrimination time.

Therefore, even if any proper discrimination time is employed, thereremains a risk that a temporal interruption of job data due to a longtime lapse accidentally took place is erroneously discriminated to beinterruption of job data that cannot be overcome.

A case will now be described in which a job, that can be continued, isended by the printer apparatus.

If a job is forcibly stopped due to job time out, the page, which hasbeen left in the printer, and on which an image is being formed thereon,is discharged in the foregoing state or the image forming process iscanceled.

Also data, such as fonts, downloaded and registered from the hostcomputer for use in the printing operation, is generally deleted.

Furthermore, the set environment, such as the size of the paper and thenumber of lines per page are restored to the default state.

As a result of the foregoing forcible stop of the job, the environmentand the like used in the job are completely reset in order to perform anext job.

An assumption is made here that following job data is supplied at amoment the job time out process is substantially ended.

Since the host computer does not know that the printer apparatus hasbeen reset due to the forcible job completion process, the host computerprepares following job data, and transfers the same as the continuationof the job data, which has been transferred.

However, the subject job process has been ended in the printerapparatus, and the registered fonts required to perform the job, theenvironment of the printer and intermediately formed image data arecleared.

However, the job data processed by the host computer is described on anassumption that the foregoing factors are left in the printer apparatus.

For example, the registered font pattern is intended to be used, acommand for ordering the paper size is omitted upon a consideration thatit has been ordered yet, and following images are formed upon aconsideration that the pages, on which images have been formed yet, areleft.

However, the foregoing factors have been cleared in the printerapparatus, thus causing the document output to be made disordered.Depending upon the situation, following setting of the printer ischanged to an incorrect state, thus raising a risk that following jobsencounters a problem that correct images cannot be formed, as well thejob, which is being processed.

As described above, in the conventional job time out process, even ifthe job is forcibly stopped due to job time out, information cannot becommunicated between the host computer and the printer apparatus. As aresult, there arises a problem in that a most proper job time outprocess cannot be performed.

SUMMARY OF THE INVENTION

In the viewpoint above, an object of the present invention is to providea printer apparatus and a method of controlling the same, in which thehost computer is able to accurately and reliably recognize the state ofthe printer apparatus.

In order to achieve the foregoing object, according one aspect of thepresent invention, there is provided a printer apparatus for performinga printing process in accordance with process demands from a datasource, comprising: receiving means for receiving process demands;assigning means for assigning a peculiar identifier to each processdemand received by the receiving means; identifier returning means forreturning, to a data source, the identifiers assigned by the assigningmeans; and information returning means for returning, to the datasource, information, which is a response indicating completion of theprocess, the demand of which has been received by the receiving means,the information being returned together with the identifier assigned tothe process demand.

According to another aspect of the present invention, there is provideda printer system in which a data source and a printer are connected toeach other, comprising: a data source including identifier generatingmeans for generating an identifier peculiar to each process demand, andtransmitting means for transmitting the process demand together with theidentifier; and a printer apparatus including receiving means forreceiving the process demand from the data source together with thepeculiar identifier to the process demand, identifier returning meansfor returning, to the data source, a response to the process demand,received from the receiving means, together with the identifier peculiarto the process demand, and information returning means for returninginformation indicating completion of the process demanded with theprocess demand together with the identifier peculiar to the processdemand.

According to another aspect of the present invention, there is provideda printer system in which a data source and a printer are connected toeach other, comprising: a data source including first time measuringmeans for measuring time, time storing means for storing time at which aprocess demand has been generated, and transmitting means fortransmitting the process demand; and a printer apparatus includingreceiving means for receiving the process demand from the data source,second time measuring means for measuring time, and returning means forreturning, to the data source, information indicating completion of theprocess, the demand of which has been received by the receiving means,together with time, at which the process demand has been received by thereceiving means.

According to another aspect of the present invention, there is provideda method of controlling a printer apparatus for performing a printingprocess in accordance with a process demand from a data source,comprising the steps of: receiving process demands; assigning anidentifier peculiar to each of process demands received in the receivingstep; returning, to the data source, identifiers assigned in theassigning step; and returning, to the data source, informationindicating completion of the process, the demand of which has beenreceived in the receiving step, together with the identifier assigned tothe process demand.

According to another aspect of the present invention, there is provideda method of controlling a printer system, in which a data source and aprinter are connected to each other, comprising the steps of: generatingan identifier peculiar to each of process demands; transmitting theprocess demand together with the identifier; receiving the processdemand transmitted in the transmitting step together with the peculiaridentifier; returning the identifier in such a manner that a responseindicating completion of a process, the process demand of which has beenreceived in the receiving step, is returned to the data source togetherwith the identifier peculiar to the process; and returning informationof a response to the process demand together with the identifierpeculiar to the process demand.

According to another aspect of the present invention, there is provideda method of controlling a printer system, in which a data source and aprinter are connected to each other, comprising the steps of: storingtime, at which a process demand has been generated, by reading the timefrom a first timer; transmitting the process demand; receiving theprocess demand transmitted in the transmitting step; and returning, tothe data source, response information indicating completion of theprocess demand received in the receiving step in such a manner thattime, at which the process demand has been received in the receivingstep, is read, and the read time is also returned when the responseinformation is returned.

In order to achieve the foregoing object, according to one aspect of thepresent invention, there is provided a printer apparatus that analyzesoutput data received from a host computer to perform an output process,comprising: means that receives output data from the host computer toadministrate one set of the output data as a unit of one job; means thatautomatically assigns administration ID information to each job, addsthe administration ID to the job to perform administration, andimmediately transmits the administration ID information assigned to onereceived job to the host computer; means that analyzes aprinter-language command described in the job to instruct an imageforming and output process, a printer apparatus control process and aprocess of responding status to the host computer; means for performingprinting out, control in accordance with the command to form and outputan image and the apparatus control command; means for investigating astate of the printer apparatus and a state of a document output inaccordance with the command for the status response issued to the hostcomputer; means for generating status response data in which theadministration ID information assigned to the job, which is beingperformed, is added to information of a result of the investigation; andmeans for transmitting the status response to the host computer througha bidirectional interface.

According to another aspect of the present invention, there is provideda printer apparatus that analyzes output data received from a hostcomputer to perform an output process, comprising: means that receivesoutput data from the host computer to administrate one set of the outputdata as a unit of one job; means that receives administration IDinformation for one job from the host computer and that adds theadministration ID information to the job in the job units to performadministration; means that analyzes a printer-language command of thejob to instruct an image forming and output process, a printer apparatuscontrol process and a process of responding status to the host computer;means for performing printing out and control in accordance with thecommand to form and output an image and the apparatus control command;means for investigating a state of the printer apparatus and a state ofa document output in accordance with the command for the status responseissued to the host computer; means for generating status response datain which the administration ID information assigned to the job, which isbeing performed, is added to information of a result of theinvestigation; and means for transmitting the status response to thehost computer through a bidirectional interface.

According to another aspect of the present invention, there is provideda printer apparatus that analyzes output data received from a hostcomputer to perform an output process, comprising: means that receivesoutput data from the host computer to administrate one set of the outputdata as a unit of one job; means that adds an administration ID to eachjob to administrate the jobs; means that analyzes a printer-languagecommand described in the job to instruct an image forming and outputprocess, a printer apparatus control process and a process of respondingstatus to the host computer; means for performing printing out andcontrol in accordance with the command to form and output an image andthe apparatus control command; means for investigating the state of theprinter apparatus and the state of a document output in accordance withthe command for the status response issued to the host computer; meansfor generating status response data in which the administration IDinformation assigned to the job, which is being performed, is added tothe investigated status; means for discriminating whether or not theinvestigated status must be transmitted to all jobs in place oftransmitting the same to each job; means for adding informationindicating importance to the status response that must be transmitted toall jobs; and means for transmitting the status response to the hostcomputer through a bidirectional interface.

According to another aspect of the present invention, there is provideda printer apparatus that analyzes output data received from a hostcomputer to perform an output process, comprising: means that receivesoutput data from the host computer to administrate one set of the outputdata as a unit of one job; means that adds an administration ID to eachjob to administrate the jobs; means that analyzes a printer-languagecommand described in the job to instruct an image forming and outputprocess, a printer apparatus control process and a process of respondingstatus to the host computer; means for performing printing out andcontrol in accordance with the command to form and output an image andthe apparatus control command; means for investigating the state of theprinter apparatus and the state of a document output in accordance withthe command for the status response issued to the host computer; meansfor generating status response data in which the administration IDinformation assigned to the job, which is being performed, is added tothe investigated status; means for discriminating whether or not theinvestigated status is not information that must be transmitted to alljobs, but is information peculiar to each job; means for addinginformation indicating peculiar status to a status response that may betransmitted to each job; and means for transmitting the status responseto the host computer through a bidirectional interface.

According to another aspect of the present invention, there is provideda printer apparatus that analyzes output data received from a hostcomputer to perform an output process, comprising: means that receivesoutput data from the host computer to administrate one set of the outputdata as a unit of one job; means that adds an administration ID to eachjob to administrate the jobs; means that analyzes a printer-languagecommand described in the job to instruct an image forming and outputprocess, a printer apparatus control process and a process of respondingstatus to the host computer; means for performing printing out andcontrol in accordance with the command to form and output an image orthe apparatus control command; means for investigating the state of theprinter apparatus and the state of a document output in accordance withthe command for the status response issued to the host computer; meansfor generating status response data in which the administration IDinformation assigned to the job, which is being performed, is added tothe investigated status; means for discriminating whether or not theinvestigated status must be transmitted to all jobs in place oftransmitting the same to each job, or discriminating whether or not theinvestigated status is not information that must be transmitted to alljobs, but is information peculiar to each job; means for addinginformation indicating importance to the status response that must betransmitted to all jobs, or for adding information indicating peculiarstatus to the status response that may be transmitted to each job; andmeans for transmitting the status response to the host computer througha bidirectional interface.

According to another aspect of the present invention, there is provideda printer apparatus that analyzes output data received from a hostcomputer to perform an output process, comprising: means that receivesoutput data from the host computer to administrate one set of the outputdata as a unit of one job; means that analyzes a printer-languagecommand described in the job to instruct an image forming and outputprocess, a printer apparatus control process and a process of respondingstatus to the host computer; means for performing printing out andcontrol in accordance with the command to form and output an image andthe apparatus control command; means for investigating the state of theprinter apparatus and the state of a document output in accordance withthe command for the status response issued to the host computer so as toissue status response data; means that supervises a state where each jobdata is received to measure time taken from interruption of the jobdata; means for forcibly stopping the job as job time out if the jobdata interrupts for a predetermined time; means having a structure thatif job time out takes place, then a status response indicatinggeneration of the job time out is issued; and means for transmitting thestatus response to the host computer through a bidirectional interface.

According to another aspect of the present invention, there is provideda printer apparatus that analyzes output data received from a hostcomputer to perform an output process, comprising: means that receivesoutput data from the host computer to administrate one set of the outputdata as a unit of one job; means that analyzes a printer-languagecommand described in the job to instruct an image forming and outputprocess, a printer apparatus control process and a process of respondingstatus to the host computer; means for performing printing out andcontrol in accordance with the command to form and output an image andthe apparatus control command; means for investigating the state of theprinter apparatus and the state of a document output in accordance withthe command for the status response issued to the host computer so as toissue status response data; means that supervises a state where each jobdata is received to measure time taken from interruption of the jobdata; means that discriminates that job time out takes place if job datainterrupts for a predetermined time, and that issues a status responsefor inquiring whether or not the job may be forcibly stopped; means thatforcibly stops the job if a response permits the job time out process tobe performed, and that continues the job if the response inhibits thejob time out to be performed; and means for transmitting the statusresponse to the host computer through a bidirectional interface.

According to another aspect of the present invention, there is provideda printer apparatus that analyzes output data received from a hostcomputer to perform an output process, comprising: means that receivesoutput data from the host computer to administrate one set of the outputdata as a unit of one job; means that analyzes a printer-languagecommand described in the job to instruct an image forming and outputprocess, a printer apparatus control process and a process of respondingstatus to the host computer; means for performing printing out andcontrol in accordance with the command to form and output an image andthe apparatus control command; means for investigating the state of theprinter apparatus and the state of a document output in accordance withthe command for the status response issued to the host computer so as toissue status response data; means that supervises a state where each jobdata is received to measure time taken from interruption of the jobdata; means that discriminates that job time out takes place if job datainterrupts for a predetermined time, and that issues a status responsefor alarming that the job will be forcibly stopped; means that continuesthe job if the host computer immediately transmits following job data,and that forcibly stops the job if the host computer does not transmitfollowing job data; and means for transmitting the status response tothe host computer through a bidirectional interface.

Other and further objects, features and advantages of the invention willbe evident from the following detailed description of the preferredembodiments in conjunction with the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is block diagram showing the structure of a page printerapparatus according to first and second embodiments of the presentinvention;

FIG. 2 is a schematic view showing an improved status response processaccording to the first embodiment;

FIG. 3 is a flow chart showing the operation of a data-receiptadministration portion of the printer apparatus according to the firstembodiment;

FIG. 4 is a flow chart showing the operation of a command process in theprinter apparatus according to the first embodiment;

FIG. 5 is a schematic view showing an improved status response processaccording to the second embodiment;

FIG. 6 is a flow chart showing the operation of a data-receiptadministration portion according to the second embodiment;

FIG. 7 is a schematic view showing an example of a conventional statusresponse process;

FIG. 8 is a schematic view showing an example of the conventional statusresponse process;

FIG. 9 is a block diagram showing the structure of a page printerapparatus according to third, fourth and fifth embodiments of thepresent invention;

FIG. 10 is a schematic view showing an improved status response processaccording to the third embodiment;

FIG. 11 is a flow chart showing the operation of a data-receiptadministration portion of the printer apparatus according to the thirdembodiment;

FIG. 12 is a flow chart showing the operation of a data-receiptadministration portion of the printer apparatus according to the thirdembodiment;

FIG. 13 is a schematic view showing an improved status response processaccording to the fourth embodiment;

FIG. 14 is a flow chart showing the operation of a data-receiptadministration portion according to the fourth embodiment;

FIG. 15 is a schematic view showing an improved status response processaccording to the fifth embodiment;

FIG. 16 is a flow chart showing the operation of a data-receiptadministration portion according to the fifth embodiment;

FIG. 17 is a cross sectional view showing a laser beam printer;

FIG. 18 is a diagram showing an ink jet printer;

FIG. 19 is a block diagram showing the structure of a page printerapparatus according to sixth and seventh embodiments of the presentinvention;

FIG. 20 is a schematic view showing an improved status response processaccording to the sixth embodiment of the present invention;

FIG. 21 is a block diagram showing the structure of a portion of a hostcomputer relating to the present invention;

FIG. 22 is a flow chart showing a command process in the printerapparatus according to the sixth embodiment of the present invention;

FIG. 23 is a schematic view showing an improved status response processaccording to the seventh embodiment of the present invention;

FIG. 24 is a flow chart showing the operation of a command processaccording to the seventh embodiment of the present invention;

FIG. 25 is a schematic view showing an example of a usual output job;

FIG. 26 is a schematic view showing an example of a conventional statusresponse process;

FIG. 27 is a schematic view showing an improved status response processaccording to an eighth embodiment of the present invention;

FIG. 28 is a flow chart showing the operation of a command process in aprinter apparatus according to the eighth embodiment of the presentinvention;

FIG. 29 is a flow chart showing the operation of the host computeraccording to the eighth embodiment of the present invention;

FIG. 30 is a schematic view showing an improved status response processaccording to a ninth embodiment of the present invention;

FIG. 31 is a flow chart showing the operation of a command processaccording to the ninth embodiment of the present invention;

FIG. 32 is a flow chart showing the operation of the process of the hostcomputer according to the ninth embodiment of the present invention;

FIG. 33 is a schematic view showing an improved status response processaccording to a tenth embodiment of the present invention;

FIG. 34 is a flow chart showing the operation of a command processaccording to the tenth embodiment of the present invention;

FIG. 35 is a flow chart showing the operation of the host computeraccording to the tenth embodiment of the present invention;

FIG. 36 is a schematic view showing an example of a status responseprocess according to the sixth and seventh embodiments of the presentinvention;

FIG. 37 is a flow chart showing the operation of a status responseprocess in the host computer according to the sixth and seventhembodiments of the present invention;

FIG. 38 is a block diagram showing the structure of a page printerapparatus according to an eleventh embodiment of the present invention;

FIG. 39 is a flow chart showing the operation of a command process in aprinter apparatus according to the eleventh embodiment of the presentinvention;

FIG. 40 is a flow chart showing the operation of a command processaccording to a twelfth embodiment of the present invention;

FIG. 41 is flow chart showing the operation of a command processaccording to a thirteenth embodiment of the present invention; and

FIG. 42 is a schematic view showing an example of a job time outprocess.

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment

A first embodiment of the present invention will now be described withreference to the drawings.

FIG. 1 is a block diagram showing the structure of a printer apparatusaccording to this embodiment.

In this embodiment, the description will be made about a page printer.Referring to FIG. 1, reference numeral 1 represents a host computer,which generates output data, such as characters and graphics, and avariety of control commands, and which generates a command for thestatus response for recognizing a variety of information items of theprinter apparatus, in order to input the foregoing data and commands toa printer apparatus 2 which is the main portion of an output apparatus.

The host computer 1 and the printer apparatus 2 are connected to eachother through a bidirectional interface so that data can be transferredfrom the host computer 1 to the printer apparatus 2, and data can bereturned from the printer apparatus 2 to the host computer 1.

In the printer apparatus 2, reference numeral 3 represents adata-receipt administration portion that receives data, such ascharacters and graphics, the various control commands and the commandfor the status response, which are supplied from the host computer 1, soas to administrate the data and commands. The data-receiptadministration portion 3 has a receiving buffer for receiving andtemporarily storing data from the host computer 1.

When the data-receipt administration portion 3 receives data or acontrol command or a command for the status response from the hostcomputer 1, the data-receipt administration portion 3 automaticallyassigns administration ID to each command.

The administration ID acts to distinguish a command from another commandand is, for example, a number given in accordance with the sequentialorder of command receipt or individual characters. Even if the contentsof the commands are the same, all administration IDs must be differentfrom one another. The administration ID assigned to each command is, ascommand administration ID information, added to each command of receiveddata, and administration of the commands is performed.

Simultaneously, the data-receipt administration portion 3 immediatelyreturns, to the host computer 1, the command administration IDinformation through a bidirectional interface.

The command administration ID information is immediately returned in thesequential order of the command receipt.

Reference numeral 4 represents a printer-language analyzing portion thatanalyzes the detailed contents of a command, and that instructs thecorresponding control to be performed in accordance with the contents ofthe command.

The printer-language analyzing portion 4 sequentially receives thecommands stored in the data-receipt administration portion 3, andinvestigates the contents of the commands in accordance with thedescription rule of the printer language so as to discriminate whatprocess is demanded to be performed.

If a result of the discrimination indicates a command for formingcharacters, graphics or images, the printer language analyzing portion 4commands an image-forming and output portion 5 to form and output animage.

If the result indicates a command for controlling the printer apparatus2, the printer-language analyzing portion 4 commands a printer-apparatuscontrol portion 6 to perform a corresponding control.

If the result requires a status response, the printer language analyzingportion 4 issues, to a status-response processing portion 7, a commandfor a status response.

Reference numeral 5 represents the image-forming and output portion thatforms and develops characters or images, to be printed out from theprinter apparatus 2, so as to output the formed and developed charactersor images.

In the image-forming and output portion 5, a corresponding characterpattern is formed, or a graphic is calculated or formed, or image datais developed in accordance with the image-forming and output commandfrom the printer language analyzing portion 4, and transmits, to theprinter engine 8, the developed data to be output.

The printer engine 8 is an apparatus, such as a laser beam printerengine, that uses a procedure of an electrophotographic method or thelike to perform a printing out process in accordance with the developedimage received from the image-forming and output portion 5.

Reference numeral 6 represents the printer-apparatus control portionthat controls and administrates the printer apparatus 2, such that itselects paper to be used and initializes the printer apparatus 2, inaccordance with the printer-apparatus control command from theprinter-language analyzing portion 4.

Reference numeral 7 represents a status-response processing portion thatinvestigates the corresponding environment of the printer apparatus 2 inaccordance with the command for the status response from theprinter-language analyzing portion 4.

A variety of contents are investigated, for example, information aboutvarious fonts, contents of image forming functions, whether or not datacan be received, the status of the printer apparatus 2 and the state ofprogress of the printing out process.

The status-response processing portion 7 investigates the variousenvironments of the printer apparatus 2 so as to prepare status responseinformation, which indicates the contents of the investigatedenvironment, the status response information being formed into acharacter string or the like.

At this time, the printer apparatus 2 adds, to the response information,administration ID information, assigned by the data-receiptadministration portion 3 to the command for the status response, whichhas caused the foregoing response.

Then, the status response information is transmitted to adata-transmission administration portion 9.

When the data-transmission administration portion 9 has received thestatus response information returned from the status-response processingportion 7, the data-transmission administration portion 9 temporarilystores it in a transmitting buffer or the like to return a statusresponse, to which the administration ID has been added, to the hostcomputer 1 at proper timing for the bidirectional interface.

FIG. 2 shows an example of the status response performed in a case wherethe demand and response sequence shown in FIG. 7 is performed in thesystem according to this embodiment. An assumption is made here that thehost computer 1 has issued, to the printer apparatus 2, commands for thestatus response, such as (1) “notify discharge of the page, which isbeing printed”, (2) “send information about the number of fonts amongthe fonts included in the printer apparatus 2 that are larger than 12points”, and (3) send information whether or not the printer apparatus 2is able to receive data at present, the foregoing commands for thestatus response being sequentially issued in the foregoing order andincluded in document output data.

When the printer apparatus 2 according to this embodiment has receivedthe foregoing commands for the status response, the data-receiptadministration portion 3 immediately and sequentially assigns receivedcommand administration IDs.

The data-receipt administration portion 3 administrates the commands inthe form in which the assigned administration ID information is added tothe command.

Assumptions are made that the administration command ID assigned to thecommand (1) is “1339”, that assigned to the command (2) is “1340” andthat assigned to the command (3) is “1341”.

As described above, the status responses cannot always be returned inthe sequential order of the commands for status response depending uponthe state of the printer apparatus 2 or the contents of the response. Anassumption is made here that the status response corresponding to thecommand (3) could be immediately returned to the host computer 1(response (3′)).

At this time, the data-transmission administration portion 9 returns, tothe host computer 1, information in the form in which the administrationID information assigned to the command is added to ordinary statusresponse information.

For example, the administration ID information “1341” assigned to thereceived command for the status response is, as exemplified in response(3′), added in front of the response data which will be then returned.

When retrieval of the fonts (command (2)) has been completed, the statusresponse is, in the form in response (2′), returned to the host computer1.

After discharge of the page has been completed finally, the statusresponse corresponding to command (1) is, in the form of response (1′),returned.

The host computer 1, that receives the status response, stores theadministration ID returned by the printer apparatus 2 while beingautomatically assigned to the command for the status response issued bythe host computer 1.

For example, the host computer 1 stores, as the ID of the command (3),the command administration ID “1331”, which has been immediatelyreturned from the printer apparatus 2 when the host computer 1 hasissued the command (3).

When the status response has been returned from the printer apparatus 2,the command administration ID added to the status response is checked,and a corresponding command administration ID stored in the hostcomputer 1 is searched for.

As shown in FIG. 2, information of the administration ID “1341”, towhich the command is assigned, is added to the response (3′).

In the viewpoint of the sequential order of issuing commands, responses(2′) and (1′) can be returned prior to the response (3). However, adiscrimination can be made that the response made first is not theresponse to command (1) or command (2), but is the response to thecommand (3) in accordance with the added command administration IDinformation.

Thus, addition of information of the administration ID assigned to thecommand to the conventional status response to be returned enablescorrespondence between status responses and the commands for statusresponse to be estimated.

Although this embodiment has been described about the structure in whichthe serial No. type ID is used as the administration ID information, thetype of the ID is not limited.

The present invention is not limited to the type of the commandadministration ID so far as the printer apparatus is able to makepresentation of the ID to the host computer.

The administration of the assignment of the administration ID to eachcommand, which is performed by the data-receipt administration portion3, may be performed for only the command to which the status response ismade or may be performed for all commands in order to simplify checkingof the commands.

If administration ID information for identifying the command for astatus response can be added to the status response when the statusresponse is returned, the type of the data administration is notlimited.

FIG. 3 is a flow chart of the operation of the printer apparatus 2according to this embodiment which illustrates a process in which thedata-receipt administration portion 3 receives data from the hostcomputer 1 to administrate the data.

Initially, the data-receipt administration portion 3 receives, from thehost computer 1, data codes indicating commands for forming an image,for control and for status response (step S301).

The data-receipt administration portion 3 supervises the transmitteddata codes, discriminates the end of one command, and stores eachcommand in the receiving buffer (step S302).

A command administration ID is assigned to each of the thus-receivedcommands (step S303).

Then, the command administration, assigned in step S303, is immediatelyreturned to the host computer 1 through the bidirectional interface(step S304).

The data codes are administrated in command units, and the data codesare, together with the command administration ID, temporarily stored inthe receiving buffer so as to administrate them (step S305).

When receipt of one command has been completed, the operation returns tostep S301, in which a next command is received and a similar process isrepeated.

As a result of a sequence of the processes above, the commandstransmitted from the host computer 1 are, together with the commandadministration ID information, stored and administrated by thedata-receipt administration portion 3.

The foregoing sequential processes are performed immediately after acommand has been issued from the host computer 1. Since the foregoingsequential processes are frequently performed individually from otherprocesses by a multitask method or the like, the processes are free frominfluences of, for example, a state where other processes are performed.Therefore, the commands can immediately be administrated in thesequential order of the command receipt.

FIG. 4 is a flow chart of a process in which the printer languageanalyzing portion 4 processes data in command units and performs imageforming, control and status response processes.

Initially, the printer-language analyzing portion 4 periodicallysupervises the receiving buffer and waits for supply of data in commandunits by the operation of the data receipt administration portion 3 asillustrated in the flow chart shown in FIG. 3. When data has beendetected, the data is received in command units (step S401).

Then, the type of the commanded processes is discriminated (step S402).If the image forming control has been commanded, the printer-languageanalyzing portion 4 transmits the foregoing command to the image-formingand output portion 5 so that a process for forming and developing animage, such as corresponding characters, graphics or images, isperformed, thus causing printing to be performed (step 5403).

If the command is a command to control the printer apparatus 2, theprinter-language analyzing portion 4 transmits the command to theprinter-apparatus control portion 6 so that the printer apparatus 2 iscontrolled as commanded (step S404).

If the command is a command for the status response, theprinter-language analyzing portion 4 transmits the foregoing command tothe status-response processing portion 7. Thus, the status-responseprocessing portion 7 investigates the corresponding environments of theprinter apparatus 2 (step S405).

The foregoing investigation cannot immediately be performed sometimesbecause a large quantity of information must be searched or the state ofthe printer apparatus 2 has been changed or due to the timing of theoperation. In the foregoing case, all processes are not interrupted, butthe employed multitask method enables the foregoing investigation to beperformed simultaneously with performing the other data process. Then,completion of the investigation is waited for.

After the investigation has been completed, a result of theinvestigation is converted into status-response data format information,such as a character string or the like. At this time, the printerapparatus 2 adds the command ID assigned to the command for the statusresponse to information about the investigation so that response data inthe form of a character string or the like in the status response dataformat is prepared (step S406).

The status response data in the form, in which the commandadministration ID is added, is sent to the data transmissionadministration portion 9 so as to be temporarily stored in thetransmitting buffer or the like, followed by being returned to the hostcomputer 1 at the timing of the bidirectional interface (step S407).

The printer-language analyzing portion 4 receives a next command fromthe receiving buffer, analyzes the same and repeats the foregoingprocess.

As a result of the foregoing process, the host computer 1 issues acommand for a status response. When the host computer 1 receives astatus response corresponding to the command therefrom, the hostcomputer 1 is able to recognize the command administration ID previouslyassigned to the command for the status response and stored in theprinter apparatus 2. Furthermore, a reference to the commandadministration ID of the command for the status response can be made asthe information of the returned status response. Therefore, even if thestatus responses are not returned out of the sequential order, or evenif a long time has undesirably taken to return the status response, thecorrespondence between the returned status response and the command forthe status response can easily be discriminated. Thus, the state of theprinter apparatus can reliably be detected by the host computer 1.

FIG. 17 is a diagram of the structure of a laser beam printer for use asthe printer engine 8 of this embodiment.

Referring to FIG. 17, reference numeral 740 represents a body of a laserbeam printer (LBP) that forms an image on recording paper, serving as arecording medium, in accordance with a supplied character pattern or thelike. Reference numeral 700 represents an operation panel havingoperation switches and LED display units disposed thereon. Referencenumeral 701 represents a printer control unit for totally controllingthe LBP 740 and for analyzing character pattern information or the like.The printer control unit 701 mainly converts character patterninformation into a video signal to transmit the video signal to a laserdriver 702.

The laser driver 702 is a circuit for operating a semiconductor laserbeam unit 703 that, in response to the supplied video signal, turnson/off a laser beam 704 emitted by the semiconductor laser beam unit703. The laser beam 704 is swung laterally by a rotational polygonalmirror 705 to scan the surface of an electrostatic drum 706. As aresult, an electrostatic latent image of the character pattern is formedon the electrostatic drum 706. The latent image is developed by adeveloping unit 707 disposed around the electrostatic drum 706, followedby being transferred onto the recording paper. The recording paper iscut sheets that are accommodated in a paper cassette 708 loaded in theLBP 740 so as to be introduced into the body of the LBP 740 by a paperfeeding roller 709 and conveyance rollers 710 and 711, followed by beingsupplied to the electrostatic drum 706.

Although the printer engine according to this embodiment is the laserbeam printer, the present invention is not limited to this. The presentinvention can be applied to, for example, an ink jet printer as will nowbe described.

<Schematic Structure of the Apparatus Body>

FIG. 18 is a schematic view of an ink jet recording apparatus URA towhich the present invention can be applied. Referring to FIG. 18, acarriage HC, that are engaged to a spiral groove 5004 of a lead screw5005, which is, through 10 power transmission gears 5011 and 5009,rotated in synchronization with a drive motor 5013, has a pin (notshown) so as to be reciprocated in directions indicated by arrows a andb. The carriage HC has an ink jet cartridge UC mounted thereon.Reference numeral 5002 represents a paper-retaining plate for pressingpaper against a platen 5000 in the direction in which the carriage HC ismoved. Reference numerals 5007 and 5008 represent photocouplers that arehome-position detection means that detects presence of a lever 5006 ofthe carriage HC in the foregoing region to, for example, switch therotational direction of a motor 5013. Reference numeral 5016 representsa member for supporting a capping member 5022 for capping the frontsurface of a recording head. Reference numeral 5015 represents a suckingmeans for sucking the inside of the cap member 5022 so that therecording head is recovered by sucking the inside of the capping member5022 through an opening 5023 in the capping member 5022. Referencenumeral 5017 represents a cleaning blade, and 5019 represents a memberenabling the cleaning blade 5017 to be moved back and forth. Thecleaning blade 5017 and the member 5019 are supported by a support plate5018 of the body of the ink jet recording apparatus URA. As a matter ofcourse, the cleaning blade 5017 is not limited to the foregoing blade,but a known cleaning blade may be used in this embodiment. Referencenumeral 5021 represents a lever for starting recovering operation bysucking the inside of the capping member 5022. When a cam 5020, thatengages to the carriage HC, is moved, the lever 5021 is moved, causingthe rotation force of the drive motor 5013 to be transmitted through aknown transmission means, such as a clutch and so forth. The capping,cleaning and suction recovery operations are arranged to be performed atcorresponding positions due to the operation of the lead screw 5005 whenthe carriage HC has been moved to the home-position portion. However,any arrangement may be employed in the present invention so far as theforegoing operations are performed at predetermined timings.

Second Embodiment

A second embodiment of the present invention will now be described withreference to the drawings. In this embodiment, the commandadministration IDs are not automatically assigned by the data-receiptadministration portion 3, but the commands are administrated by usingcommand administration IDs sent from the host computer 1 together withthe various commands and specified by the host computer 1.

The flow of the operations of this embodiment will now be described withreference to FIG. 5.

In the second embodiment, the host computer 1 adds administration ID foridentifying the commands to each command when the host computer 1 issuesa command.

The administration ID may be added to all commands or the same may beadded to only the command that requires a status response.

Even if the type of the commands are the same, the administration IDsmust be individual IDs. When the data receipt administration portion 3has received various commands and command administration IDs assigned tothe commands, the data-receipt administration portion 3 stores them incommand units, and administrates them while adding the sent commandadministration IDs.

The data-receipt administration portion 3 does not assign the commandadministration IDs.

The following process is the same as that according to the firstembodiment.

That is, the command administration IDs added to the status responsesare not assigned by the printer apparatus 2, but are assigned by thehost computer 1.

FIG. 6 is a flow chart of the operation of the data-receiptadministration portion 3 according to this embodiment.

Initially, commands for forming images and performing controls andrequiring status responses, and data codes, such as the administrationIDs assigned to the commands by the host computer 1 supplied from thehost computer 1 are received by the data-receipt administration portion3 (step S601).

The data-receipt administration portion 3 supervises the supplied datacodes, and discriminates the end of one command to store the command inthe receiving buffer (step S602).

Furthermore, the data-receipt administration portion 3 takes the commandadministration ID specified to the command by the host computer 1 (step5603).

The data codes are administrated in command units such that the datacodes are, together with the command administration IDs taken in stepS603, temporarily stored and administrated in a region in the receivingbuffer or the like (step S604).

When receipt of one command has been completed, the operation returns tostep S601 so that a next command is received, and a similar process isrepeated.

As a result of the foregoing process, when the host computer issues acommand for the status response and receives the status responsecorresponding to the command, the command administration ID foridentifying the command for the status response, which has beenpreviously specified by the host computer enables the host computer torefer to the command administration ID information of the specifiedcommand for the status response as the information of the returnedstatus response. Therefore, even if the status responses are notreturned out of the sequential order, or even if a long time hasundesirably been taken to return the status response, the correspondencebetween the returned status response and the command for the statusresponse can easily be discriminated. Thus, the state of the printerapparatus can reliably be detected by the host computer.

Third Embodiment

A third embodiment of the present invention will now be described withreference to the drawings.

FIG. 9 is a block diagram showing the structure of a printer apparatusaccording to this embodiment.

In this embodiment, a page printer is described.

Referring to FIG. 9, reference numeral 1 represents a host computer,which generates output data, such as characters and graphics, and avariety of control commands, and which generates a command for thestatus response for recognizing a variety of information items of aprinter apparatus 2′ in order to input the foregoing data and commandsto the printer apparatus 2′ which is the main portion of an outputapparatus.

The host computer 1 and the printer apparatus 2′ are connected to eachother through a bidirectional interface so that data can be transferredfrom the host computer 1 to the printer apparatus 2′ and data can bereturned from the printer apparatus 2′ to the host computer 1.

In the printer apparatus 2′ reference numeral 3 represents adata-receipt administration portion that receives output data, such ascharacters and graphics, the various control commands and the commandfor the status response, which are supplied from the host computer 1, soas to administrate the data and commands.

The data-receipt administration portion 3 has a receiving buffer forreceiving and temporarily storing data from the host computer 1.

Reference numeral 10 represents a timer administration portion foradministrating the time in the printer apparatus 2′. The timeradministration portion 10 has a clock that counts the time to recognizetime passing in the inside of the printer apparatus 2′. The clock isadministrated with a usual time, for example, the standard time to countthe same times as that outside the printer apparatus 2′.

When the data-receipt administration portion 3 receives data, variouscontrol commands or commands for the status response from the hostcomputer 1, the data-receipt administration portion 3 demands the timeradministration portion 10 to notify the present time simultaneously withthe receipt of the data or commands.

The present time received from the timer administration portion 10 isadded to each command of the received data to administrate the time asthe received time information.

Reference numeral 4 represents a printer-language analyzing portion thatanalyzes the detailed contents of the command, and that instructs thecorresponding control to be performed in accordance with the contents ofthe command.

The printer-language analyzing portion 4 sequentially receives thecommands stored in the data-receipt administration portion 3, andinvestigates the contents of the commands in accordance with thedescription rule of the printer language so as to discriminate whatprocess is demanded to be performed.

If a result of the discrimination indicates a command for formingcharacters, graphics or images, the printer-language analyzing portion 4commands an image-forming and output portion 5 to form and output animage.

If the result indicates a command for controlling the printer apparatus2′ the printer-language analyzing portion 4 commands a printer-apparatuscontrol portion 6 to perform a corresponding control.

If the result indicates a certain status response, the printer-languageanalyzing portion 4 issues, to a status-response processing portion 7, acommand for a status response.

Reference numeral 5 represents an image-forming and output portion thatforms and develops characters or images, to be printed out from theprinter apparatus 2′ so as to output the formed and developed charactersor images.

In the image-forming and output portion 5, a corresponding characterpattern is formed, or a graphic is calculated or formed, or image datais developed in accordance with the image-forming and output commandfrom the printer-language analyzing portion 4, and transmits, to theprinter engine 8, the developed data to be output.

The printer engine 8 is an apparatus, such as a laser beam printerengine, that uses a procedure of an electrophotographic method or thelike to perform a printing out process in accordance with the developedimage received from the image-forming and output portion 5.

Reference numeral 6 represents the printer-apparatus control portionthat controls and administrates the printer apparatus 2′ such that itselects paper to be used and initializes the printer apparatus 2′ inaccordance with the printer-apparatus control command from theprinter-language analyzing portion 4.

Reference numeral 7 represents a status-response processing portion thatinvestigates the corresponding environment of the printer apparatus 2′in accordance with the command for the status response from theprinter-language analyzing portion 4.

A variety of contents are investigated, for example, information aboutvarious fonts, contents of image forming functions, whether or not datacan be received, the status of the printer apparatus 2′ and the state ofprogress of the printing output process.

The status-response processing portion 7 investigates the variousenvironments of the printer apparatus 2′ so as to prepare statusresponse information, which indicates the contents of the investigatedenvironment, the status response information being formed into acharacter string or the like.

At this time, the printer apparatus 2′ adds, to the responseinformation, information about the time, at which the command for thestatus response has been sent from the host computer 1.

Then, the status response information is transmitted to adata-transmission administration portion 9.

When the data-transmission administration portion 9 has received thestatus response information returned from the status-response processingportion 7, the data-transmission administration portion 9 temporarilystores it in a transmitting buffer or the like to return a statusresponse, to which the time information has been added, to the hostcomputer 1 at proper timing for the bidirectional interface.

FIG. 10 shows an example of the status response which is performed tocorrespond to the sequence shown in FIG. 7 in the system according tothis embodiment.

An assumption is made here that the host computer 1 has issued, to theprinter apparatus 2′ commands for the status response, such as (1)“notify discharge of the page, which is being printed”, (2) “sendinformation about the number of fonts among the fonts included in theprinter apparatus 2′ that are larger than 12 points”, and (3) sendinformation whether or not the printer apparatus 2′ is able to receivedata at present, the foregoing commands for the status response beingsequentially issued in the foregoing order and included in documentoutput data.

When the printer apparatus 2′ according to this embodiment has receivedthe foregoing commands for the status response, the data-receiptadministration portion 3 demands the timer administration portion 10 totransmit time information. The data-receipt administration portion 3administrates each command while adding the time information to thecommand.

Assumptions are made that the time at which the command (1) has beenreceived is “16:25:43”, the time at which the command (2) has beenreceived is “16:25:50” and the time at which the command (3) has beenreceived is “16:26:03”.

As described above, the status responses cannot always be returned inthe sequential order of the commands for status response depending uponthe state of the printer apparatus 2′ or the contents of the response.

An assumption is made here that the status response corresponding to thecommand (3) could be immediately returned to the host computer 1(response 3′).

At this time, the data-transmission administration portion 9 returns, tothe host computer 1, information in the form in which information of thetime at which each command has been received is added to ordinary statusresponse information items.

For example, time “16:26:03”, at which the command for the statusresponse has been received, is, as exemplified in (response 3′), addedin front of the response data which will be then returned.

When retrieval of the fonts in command (2) has been completed, thestatus response is, in the form in response (2′), returned to the hostcomputer 1.

After discharge of the page has been completed, the status responsecorresponding to command (1) is, in the form in response (1′), returned.The host computer 1, that receives the status response, stores, forexample, the time at which the host computer 1 has issued the commandfor the status response.

For example, the host computer 1 stores that the time, at which thecommand (3) has been issued, is “16:26:03”.

When the status response has been returned from the printer apparatus 2′the added command receipt time information in the printer apparatus 2′is checked, and a corresponding command issuing time stored in the hostcomputer 1 is searched for.

Information, that is, time “16:26:03”, at which the command has beenreceived by the printer apparatus 2′ is added to the response (3′) asillustrated.

In the viewpoint of the sequential order of issuing commands, responses(2′) and (1′) can be returned prior to the response (3).

However, a discrimination can be made that the response made first isnot the response to command (1) or command (2) but is the response tothe command (3) in accordance with the added receipt time information.

Thus, addition of information of the time, at which the command has beenreceived, to the conventional status response to be returned enablescorrespondence between status responses and the commands for statusresponse to be estimated.

Although this embodiment has been described about the example in whichthe minimum unit of time information is made to be in unit of seconds, afurther fine or rough unit may be employed. Furthermore, the format of“hour: minute: second” is not limited to this. For example, “hour” and“minute” are not used, but only “second” may be employed.

Furthermore, the reference time for the time information may be anyreference time.

The standard time for each country, such as the Japanese Standard Time,may be employed, or time administrated peculiarly by the subjectcomputer system may be used as the reference time.

The present invention is not limited to the type of the time, at whichthe printer apparatus has received a command, so far as the printerapparatus is able to make presentation of the foregoing time to the hostcomputer.

The administration of the receipt time information for each command,which is performed by the data-receipt administration portion 3, may beperformed for only the command to which the status response is made ormay be performed for all commands in order to simplify checking of thecommands.

If the time, at which the command for the status response has beenreceived, can be added to the status response when the status responseis returned, the type of the data administration is not limited.

FIG. 11 is a flow chart of the operation of the printer apparatus 2′according to this embodiment which illustrates a process in which thedata-receipt administration portion 3 receives data from the hostcomputer 1 to administrate the data.

Initially, the data-receipt administration portion 3 receives, from thehost computer 1, data codes indicating commands for forming an image,for control and for status response (step S111).

The data-receipt administration portion 3 immediately requires the timeradministration portion 10 to send time information (step S 12).

The data-receipt administration portion 3 supervises sent data codes todiscriminate the end of one command so as to store each command in thereceiving buffer (step S113).

As a result, the data-receipt administration portion 3 administrates thedata codes in command units in such a manner that the data codes aretemporarily stored together with the receipt time received in step S112into a receiving buffer or the like (step SI 14).

When receipt of one command has been completed, the operation returns tostep S111, in which a next command is received and a similar process isrepeated.

As a result of a sequence of the processes above, the commandstransmitted from the host computer 1 are, together with the commandreceipt time information, stored and administrated by the data-receiptadministration portion 3.

The foregoing sequential processes are performed immediately after acommand has been issued from the host computer 1. Since the foregoingsequential processes are frequently performed individually from otherprocesses by a multitask method or the like, the processes are free frominfluences of, for example, a state where other processes are performed.Therefore, the time, at which the command has been received, can beadministrated.

FIG. 12 is a flow chart of the operation of the printer apparatusaccording to this embodiment, in which the printer-language analyzingportion 4 processes data in command units and performs image formingcontrol, and status response processes.

Referring to FIG. 12, the printer-language analyzing portion 4periodically supervises the receiving buffer and waits for supply ofdata in command units by the operation of the data-receiptadministration portion 3 as shown in the flow chart shown in FIG. 11.When data has been detected, the data is received in command units (stepS121).

Then, the type of the commanded processes is discriminated (step S122).

If the image forming control has been commanded, the printer-languageanalyzing portion 4 transmits the foregoing command to the image-formingand output portion 5 so that a process for forming and developing animage, such as corresponding characters, graphics or images, isperformed, thus causing printing to be performed (step S123).

If the command is a command to control the printer apparatus 2′ theprinter-language analyzing portion 4 transmits the command to theprinter-apparatus control portion 6 so that the printer apparatus 2′ iscontrolled as commanded (step S124).

If the command is a command for the status response, theprinter-language analyzing portion 4 transmits the foregoing command tothe status-response processing portion 7. Thus, the status-responseprocessing portion 7 investigates the corresponding environments of theprinter apparatus 2′ (step S125).

The foregoing investigation cannot immediately be performed sometimesbecause a large quantity of information must be searched or the state ofthe printer apparatus 2′ has been changed or due to timing of theoperation. In the foregoing case, all processes are not interrupted, butthe employed multitask method enables the foregoing investigation to beperformed simultaneously with performing the other data process. Then,completion of the investigation is waited for.

After the investigation has been completed, a result of theinvestigation is converted into status-response data format information,such as a character string or the like.

At this time, the printer apparatus 2′ according to the presentinvention adds information about the time, at which the command for thestatus response has been received, to the information about the resultof the investigation so that response data in the form of a characterstring or the like in the status response data format is prepared (stepS126).

The status response data in the form, in which the command receiptinformation is added, is sent to the data transmission administrationportion 9 so as to be temporarily stored in the transmitting buffer orthe like, followed by being returned to the host computer 1 at thetiming of the bidirectional interface (step S127).

The printer-language analyzing portion 4 receives a next command fromthe receiving buffer, analyzes the same and repeats the foregoingprocess.

As a result of the foregoing process, when the host computer 1 issues acommand for the status response and receives a status responsecorresponding to the command therefrom, the host computer 1 is able torefer to information of the time, at which the command for the statusresponse has been received, as the information of the returned statusresponse. Therefore, even if the status responses are not returned outof the sequential order, or even if a long time has undesirably taken toreturn the status response, the correspondence between the returnedstatus response and the command for the status response can easily bediscriminated. Thus, the state of the printer apparatus can reliably bedetected by the host computer.

Fourth Embodiment

A fourth embodiment of the present invention will now be described withreference to the drawings.

In this embodiment, time information administrated by the timeradministration portion 10 according to the third embodiment is improved.

In the third embodiment, in which the time, at which the command for thestatus response has been received, is returned as additional informationto the status response. However, undesirable difference between the timeadministrated in the host computer and that administrated in the printerapparatus will make useless the added command receipt time informationaccording to the third embodiment.

Accordingly, the fourth embodiment has an additional function in which acommand to set time from the host computer is received to set the timein the printer apparatus to make coincide the two times in the hostcomputer and the printer apparatus.

Referring to FIG. 13, the operation of this embodiment will now bedescribed.

In this embodiment, prior to starting the printing job, the hostcomputer 1 issues a command to set the time in the printer apparatus 2′.

Then, the data-receipt administration portion 3 discriminates thecommand to immediately transmit information about the specified time tothe timer administration portion 10.

The timer administration portion 10 resets the time thereof inaccordance with the transmitted time information.

Then, the time in the printer apparatus 2′ is administrated inaccordance with the reset time.

That is, command receipt time information to be added to the statusresponse is made on the basis of the time administrated by the hostcomputer 1 so that the problem caused from the time difference betweenthe two apparatuses is overcome.

The other process is performed similarly to the third embodiment.

The reason why the command for setting the time issued from the hostcomputer 1 is not analyzed by the printer-language analyzing portion 4,but the same is analyzed by the data-receipt administration portion 3lies in that accuracy of the set time must be maintained by immediatelyperforming the time setting process when the command has been supplied.

For example, an assumption is made that the process performed by theprinter-language analyzing portion 4 delays the operation of setting thetime in the printer apparatus 2′ by the timer administration portion 10by three seconds from the issue of the time setting command from thehost computer 1. As a result, also time information to be added to thestatus response is delayed by three seconds. In order to prevent theforegoing problem, the foregoing structure is employed.

FIG. 14 is a flow chart of the operation of the data-receiptadministration portion 3 according to the fourth embodiment.

Initially, commands for forming various images, controls and statusresponses and data codes for setting the time administrated by theprinter apparatus 2′ from the host computer 1 are received by thedata-receipt administration portion 3 (step S141).

The data-receipt administration portion 3 discriminates as to whether ornot the transmitted information is the time setting command (step S142).

If the transmitted information is the time setting command, thedata-receipt administration portion 3 immediately transmits theforegoing command to the timer administration portion 10 to update thetime in the printer apparatus 2′ to the specified time (step S143).

Then, the operation returns to the start of the flow chart.

Then, the time to be used in the ensuing operation is administrated onthe basis of the updated time.

If the information is not the time setting command, the data-receiptadministration portion 3 immediately requires the timer administrationportion to send time information (step S144).

The data-receipt administration portion 3 supervises sent data cods todiscriminate the end of one command (step S145).

Thus, the data codes are administrated in command units and are,together with the receipt time received in step S144, temporarily storedin the receiving buffer or the like so as to be administrated (stepS146).

When receipt of one command has been completed, the operation returns tostep S141 in which a next command is received and a similar process isrepeated.

As a result, the time in the host computer 1 and that in the printerapparatus 2′ are made coincide with each other, causing the commandreceipt time information added to the status response to be made furtherreliable. Thus, when the host computer 1 issues a command for the statusresponse and receives a status response corresponding to the commandtherefrom, the host computer 1 is able to refer to information of thetime, at which the command for the status response has been received, asthe information of the returned status response. Therefore, even if thestatus responses are not returned out of the sequential order, or evenif a long time has undesirably taken to return the status response, thecorrespondence between the returned status response and the command forthe status response can easily be discriminated.

Thus, the state of the printer apparatus can reliably be detected by thehost computer.

Fifth Embodiment

A fifth embodiment of the present invention will now be described withreference to the drawings.

In this embodiment, the data-receipt administration portion 3 accordingto the third embodiment is improved.

In the third embodiment, the time, at which the command for the statusresponse has been received, is returned as additional information to thestatus response. However, time administrated in the host computer andthat administrated in the printer apparatus do not always coincide witheach other.

Therefore, there is a possibility that the comparison between the timeadministrated by the host computer 1 and time information returned bythe printer apparatus 2′ is useless.

Accordingly, the fifth embodiment has an additional function in which,when a command is received from the host computer, and the commandreceipt time has been established in the printer apparatus, timeinformation is immediately returned to the host computer to subject, toa comparison, the command receipt time information and the commandreceipt time information which will be returned while being added to thestatus response.

The flow of the operation will now be described with reference to FIG.15.

In this embodiment, when the data-receipt administration portion 3receives output data, various control commands and commands for statusresponse (commands (1), (2) and (3)) from the host computer 1, thedata-receipt administration portion 3 requires the timer administrationportion 10 to send the present time information simultaneously with theforegoing receipt. The present time received from the timeradministration portion 10 is added to each command of received data asreceipt time information so as to be administrated.

Simultaneously, information of the time, at which the command has beenreceived, is immediately returned to the host computer 1 through thebidirectional interface (responses (1′), (2′) and (3′)).

The return at this time is immediately performed in the sequential orderof the command receipt.

That is, the host computer 1 is able to confirm the time, at which thecommand issued therefrom has been received, with reference to the timeadministrated by the printer apparatus 2′ in accordance with theforegoing return.

The host computer 1 stores the returned command receipt time for theprinter apparatus 2′ for each command.

When the host computer 1 has received the status response returned afterthe receipt of the command receipt time (responses (1′), (2′) and (3′)),the command receipt time, which has been received and stored, and thecommand receipt time information added to the status response aresubjected to a comparison. Thus, the correspondence between the commandsand status responses can reliably be discriminated.

That is, the difference between the times administrated by the hostcomputer 1 and that administrated by the printer apparatus 2′ does notraise any problem.

The other process is the same as that according to the third embodiment.

FIG. 16 is a flow chart of the operation of the data-receiptadministration portion 3 according to the fifth embodiment.

Initially, data codes, such as commands for forming images, controls andstatus responses, from the host computer 1 are received by thedata-receipt administration portion 3 (step S161).

As a result, the data-receipt administration portion 3 immediatelyrequires the timer administration portion 10 to supply time information(step S162).

The data-receipt administration portion 3 supervises supplied data codesto discriminate the end of one command (step S163).

Thus, the data codes are administrated in command units and aretemporarily stored and administrated in the receiving buffer or the liketogether with the receipt time received in step S162 (step S164).

The, the command receipt time information is immediately returned to thehost computer 1 through the bidirectional interface (step S165).

When receipt of one command has been completed, the operation returns tostep S161 in which a next command is received, a next process isrepeated.

As a result, even if the time in the host computer 1 and that in theprinter apparatus 2′ do not coincide with each other, the commandreceipt time previously returned to the host computer 1 immediately whenthe command has been received enables the command receipt timeinformation added to the status response to be made further reliable.

Thus, when the host computer 1 issues a command for the status responseand receives a status response corresponding to the command therefrom,the host computer 1 is able to refer to information of the time, atwhich the command for the status response has been received, as theinformation of the returned status response. Therefore, even if thestatus responses are not returned out of the sequential order, or evenif a long time has undesirably taken to return the status response, thecorrespondence between the returned status response and the command forthe status response can easily be discriminated. Thus, the state of theprinter apparatus can reliably be detected by the host computer.

Note that the present invention may be applied to a system consisting ofa plurality of units or an apparatus comprising one unit. As a matter ofcourse, the present invention can be applied to a case where a system oran apparatus is constituted with a supplied program.

Sixth Embodiment

A sixth embodiment of the present invention will now be described withreference to the drawings.

FIG. 19 is a block diagram of the structure of a printer apparatusaccording to sixth, seventh and eighth embodiments.

In this embodiment, the description will be made about a page printer.

Referring to FIG. 19, reference numeral 1 represents a host computer,which generates output data, such as characters and graphics, and avariety of control commands, and which generates a command for thestatus response for recognizing a variety of information items of theprinter apparatus, in order to input the foregoing data and commands toa printer apparatus 2 which is the main portion of an output apparatus.

The host computer 1 and the printer apparatus 2 are connected to eachother through a bidirectional interface so that data can be transferredfrom the host computer 1 to the printer apparatus 2, and data can bereturned from the printer apparatus 2 to the host computer 1.

In the printer apparatus 2, reference numeral 3 represents adata-receipt administration portion that receives data, such ascharacters and graphics, the various control commands and the commandfor the status response, which are supplied from the host computer 1, soas to administrate the data and commands.

The data-receipt administration portion 3 has a receiving buffer forreceiving and temporarily storing data from the host computer 1.

Reference numeral 4 represents a printer-language analyzing portion thatanalyzes the detailed contents of a command, and that instructs thecorresponding control in accordance with the contents of the command.

The printer-language analyzing portion 4 sequentially receives thecommands stored in the data-receipt administration portion 3, andinvestigates the contents of the commands in accordance with thedescription rule of the printer language so as to discriminate whatprocess is demanded to be performed. If the result of the discriminationindicates a command relating to job administration, such as a commandfor starting a printing job or a completion declaration, a correspondingjob administration command is issued to a job administration portion 5.

If the command orders to form an image, such as characters or graphics,a command is issued to an image-forming and output portion 6 to form andoutput a corresponding image.

If the command orders to control the printer apparatus 2, acorresponding control command is issued to a printer-apparatus controlportion 7.

If the command orders a status response, a command for the statusresponse is issued to a status-response processing portion 8.

Reference numeral 5 represents the job administration portion.

The job administration portion 5 processes print data from the hostcomputer 1 in job units in accordance with a job administration commandfrom the printer-language analyzing portion 4. When the jobadministration portion 5 according to the present invention has receiveda printing job start declaration from the host computer 1, the jobadministration portion 5 automatically assigns an administration ID tothe job.

The administration ID is used to distinguish the job from other jobs,the administration ID being numerals assigned in the sequential order ofreceipt of the job start declaration or an independent character string.

Note that the administration ID must be different among all jobs thathave been received.

The administration ID assigned to each job is, as job-administration IDinformation, added to each job of the received output data so as to beadministrated. The job-administration ID information is stored until thecorresponding job is completed.

Simultaneously, the job administration portion 5 immediately returns thejob-administration ID information to the host computer 1 through thebidirectional interface.

The foregoing returning operation is immediately performed in thesequential order of the job receipt.

Reference numeral 6 represents an image forming and output portion forforming and developing characters, graphics and images to output them.

The image-forming and output portion 6 processes a correspondingcharacter pattern, calculates a graphic, forms an image or develop imagedata in accordance with the image forming and output command from theprinter-language analyzing portion 4, the output developed data beingthen transmitted to a printer engine 9.

The printer engine 9 is an apparatus, such as a laser beam printer, thatprints out data by using an electrophotographic method in accordancewith output development data received from the image-forming and outputportion 6.

Reference numeral 7 represents a printer-apparatus control portion thatcontrols and administrates the printer apparatus 2, such that it selectspaper to be used and initializes the printer apparatus 2, in accordancewith the printer-apparatus control command from the printer-languageanalyzing portion 4.

Reference numeral 8 represents a status-response processing portion thatinvestigates the corresponding environment of the printer apparatus 2 inaccordance with the command for the status response from theprinter-language analyzing portion 4.

A variety of contents are investigated, for example, information aboutvarious fonts, contents of image forming functions, whether or not datacan be received, the status of the printer apparatus 2 and the state ofprogress of the printing output process.

The status-response processing portion 8 investigates the variousenvironments of the printer apparatus 2 so as to prepare status responseinformation, which indicates the contents of the investigatedenvironment, the status response information being formed into acharacter string or the like.

At this time, the printer apparatus 2 adds, to the job data, in whichthe command for the status response is described, the administration IDinformation assigned by the job administration portion 5. Furthermore,the printer apparatus 2 according to the present invention comprises thestatus-response processing portion 8 that discriminates the contents ofthe status responses to judge whether or not the status responses forall jobs must be communicated as well as the status response for thejob, which is being performed. If the status response is an importantstatus response that must be communicated to all jobs, informationindicating importance is further added to the status response. Thestatus response information is transmitted to the data-transmissionadministration portion 10.

When the data-transmission administration portion 10 has received thestatus response information returned from the status-response processingportion 8, the status response information is temporarily stored in thetransmitting buffer or the like, followed by being returned to the hostcomputer 1 at a proper timing for the bidirectional interface whilebeing formed into a shape in which the administration ID information isadded.

FIG. 20 shows an example of a status response corresponding to anexample shown in FIG. 25 and according to the present invention.

An assumption is made here that a first job 1 has been sent from thehost computer 1 to the printer apparatus 2 (process 1).

The printer-language analyzing portion 4 analyzes the supplied job datain command units. If the printer-language analyzing portion 4 hasreceived a job start declaration, it transmits the job start declarationto the job administration portion 5.

The job administration portion 5 according to the present inventionstarts job administration in accordance with the transmitted job startdeclaration, and assigns job-administration ID information to the job(process 2).

The job administration portion 5 administrates each job in the form inwhich the assigned administration ID information is added.

For example, the administration is performed in such a manner that thejob-administration ID information assigned to the first Job 2 is “37”,that assigned to a next Job 2 is “38” and that assigned to a next Job 3is “39”.

The job administration portion 5 immediately transmits the assignedjob-administration ID information from the status-response processingportion 8 to the host computer 1 so that the sent Job 1 beingadministration ID “37” is transmitted (process 3).

The foregoing transmission is performed by a character string or thelike, for example, “STATUS JOB ID: 37 RECEIVED”.

As described above, the host computer 1 requires information about thevarious statuses of the printer apparatus 2.

The statuses are the sizes of paper that can be used, available fonts,the state of the printer apparatus 2, such as whether or not out ofpaper takes place, the page No. that has been discharged during thepresent output job, and whether or all pages have been discharged.

The foregoing status responses are classified into status, such asinformation about the available paper size, that can be immediatelyreturned; status, such as the state of the printer that changes alwaysand that must be returned whenever the change occurs; status, such asthe page discharge state, that must be responded after the printerengine has completed the process thereof.

Therefore, status responses are sometimes returned to the host computer1 after a long time has passed from the receipt of a command for thestatus response.

Therefore, a case will occur frequently where the first Job 1 has beencompleted in the host computer 1, and the next Job 2 has started.

Accordingly, the status-response processing portion 8 according to thepresent invention returns the status response information to the hostcomputer 1 while adding the administration ID information assigned toeach job to the usual status response information (response 5).

An assumption is made here that the third page has been printed outduring a process of output data in the Job 1. If a status of the pagedischarge has been required from the host computer 1, information aboutcompletion of the discharge of the third page must be communicated tothe host computer 1.

The status-response processing portion 8 according to the presentinvention adds, to the page discharge information, administration ID“37” of the Job 1 so that the information is expressed by a characterstring or the like, such as “STATUS JOB-ID: 37 PAGE:3 FINISHED”, and theinformation is transmitted to the host computer 1.

The host computer 1 subjects, to a comparison, the job administration IDadded to the conventional status response and the presentjob-administration ID, received at the job has been started. Thus, thehost computer 1 is able to discriminate easily the job data in which thereturned status response has been generated.

In the foregoing example case, page discharge information can bediscriminated to be information that relates to page discharge indicatedby the job-administration ID “37” in accordance with sent information“STATUS JOB-ID: 37 PAGE:3 FINISHED”.

The job-administration ID “37”, returned from the printer apparatus 2 atthe time of start of the Job 1 and assigned to the Job 1, and the ID,assigned to the foregoing status response, coincide with each other.

As a result, the host computer 1 is able to discriminate that the statusresponse does not relate to the Job 2 and Job 3, which have beenstarted.

FIG. 21 is a block diagram showing the structure of a portion of thehost computer 1 that relates to the present invention.

Referring to FIG. 21, reference numeral 1 represents the host computer,and 2 represents the printer apparatus. Reference numeral 11 representsa printing-out administration portion that totally administrates anoperation of printing out a document in accordance with an instructionfrom a user or the like.

When an instruction for printing out a document or the like has beenmade by a user or the like, the printing-out administration portion 11administrates the output of the document as one printing job. Thecontents of the instructed document are received from a document filerecorded on, for example, a hard disk 12 to transmit the contents to aprinting-data processing portion 13.

To obtain information about, for example, the printer apparatus 2,required to perform the printing job, the printing-out administrationportion 11 issues a command for the status response to the printing-dataprocessing portion 13.

The printing-data processing portion 13 converts the command for thestatus response and the contents of the document received from theprinting-out administration portion 11 into a printer-language formatthat can be recognized by the printer apparatus 2 to transmit theconverted data to a host computer-side data-transmission portion 14.

The host computer-side data transmitting portion 14 transmits thesupplied job data to the printer apparatus 2.

The printer apparatus 2 analyzes the job data to perform variousprinting processes, and returns various status responses.

The returned status responses are received by a host computer-side datareceiving portion 15 so as to be transmitted to a responded-dataanalyzing portion 16.

The responded-data analyzing portion 16 analyzes the received statusresponses to communicate their contents to the printing-outadministration portion 11.

The communicated status responses are processed as follows:

When the host computer 1 has transmitted a job, the printer apparatus 2assigns and returns a job-administration ID assigned to the job.

When the printing-out administration portion 11 has received thejob-administration ID, it discriminates that the returnedjob-administration ID is the administration ID assigned to the job whichis being processed, followed by storing the returned job-administrationID while making the same correspond to the job.

Then, the printer apparatus 2 appropriately returns status responses inaccordance with commands for the status response from the host computer1.

As described above, the foregoing status responses have information ofjob-administration IDs added thereto.

The printing-out administration portion 11 receives thejob-administration ID, as well the contents of each status response tosubject the job-administration ID added to the status response and thejob-administration ID, which has been received at the start of the job,to a comparison.

If the two job-administration IDs coincide with each other, the statusresponse has been generated during the job, which is being processed,and therefore the status response can be used. If they do not coincidewith each other, the status response has been generated during anotherjob, and therefore the status response can be ignored.

In case of a host computer capable of performing a parallel process, orin an environment in which a plurality of users or host computers areconnected, a plurality of jobs sometimes are processed simultaneously bythe host computer. Even in the foregoing case, the job-administration IDenables only the status response required for each job to be selected soas to detect the state of the printer apparatus.

As described above, information of the administration ID assigned to ajob is added to a conventional status response, followed by beingreturned, thus causing a detection to be performed that the job, duringwhich the status response has been generated, can be inferred.

When the responded-data analyzing portion 16 has received a statusresponse, the responded-data analyzing portion 16 discriminates as towhether or not information indicating that the response is an importantresponse, which relates to all jobs, is added to the status response.

In the foregoing case, a discrimination is performed as to whether ornot a character string or the like, such as “*CAUTION*” is added.

If information indicating importance is added, a judgment is performedthat the status response is not peculiar to each job, but relates to alljobs.

The contents of the status responses of all jobs are always analyzedregardless of job-administration ID information so that a variety ofcorresponding processes are performed.

If information indicating importance is not added, a judgment isperformed that the status response is peculiar to the job.

In the foregoing case, then, job-administration ID information ischecked. If the corresponding job is being processed, the statusinformation is sent to the foregoing process.

During the corresponding job, the supplied status information isanalyzed so that a variety of corresponding processes are performed.

If no corresponding job is being performed, the status information isignored.

In a case of a host computer capable of performing a parallel process,or in an environment in which a plurality of users or host computers areconnected, a plurality of jobs are sometimes performed simultaneously bythe host computer. Even in the foregoing cases, the job-administrationID and information indicating importance enable discrimination to beperformed whether the status response is peculiar to the job or the samerelates to all jobs.

Although the job-administration ID information according to thisembodiment is formed into a serial No., any ID form may be employed.

The information indicating importance is not limited to a characterstring according to this embodiment.

The essential portion of the present invention requires thatpresentation of job-administration IDs and information indicatingimportance can be made to the host computer.

FIG. 22 is a flow chart of the operation of the present invention, inwhich the printer-language analyzing portion 4 performs jobadministration processes, image forming processes, control processes andstatus-response processes.

The printer-language analyzing portion 4 receives data from thedata-receipt administration portion 3 (step S1).

Then, the process to be performed in accordance with the issued commandis discriminated (step S2).

If any job control is instructed, this command is transmitted to the jobadministration portion 5 so that a corresponding job control process isperformed. Then, a discrimination is performed whether or not thecommand is a job start declaration (step S3).

If the command declares start of the job, a job-administration ID forthe job is determined and administrated (step S4).

Then, the determined job-administration ID is immediatelystatus-responded to the host computer 1 (step S5).

If the command is a command except the job start declaration, acorresponding job administration process is performed (step S6).

If any image forming control is instructed, this command is transmittedto the image-forming and output portion 6 so that a correspondingprocess for imaging and developing characters, graphics and images isperformed, and the developed image is printed out. If the command ordersto control the printer, the command is transmitted to theprinter-apparatus control portion 7 so that a corresponding printercontrol process is performed (step S7).

If the command requires any status response, the command is transmittedto the status-response processing portion 8. The status-responseprocessing portion 8 investigates the corresponding state of theenvironment of the printer apparatus 2 (step S8).

The foregoing investigation cannot immediately be performed sometimesbecause a large quantity of information must be searched or the state ofthe printer apparatus 2 has been changed or due to the timing of theoperation. In the foregoing case, all processes are not interrupted, butthe employed multitask method enables the foregoing investigation to beperformed simultaneously with performing the other data process. Then,completion of the investigation is waited for.

After the investigation has been completed, its result is converted intostatus response data format information in the form of a characterstring or the like.

At this time, the printer apparatus 2 according to the present inventionadds, to the investigation information, job-administration IDinformation of the job requiring the response, so as to process responsedata in the form of a character string or the like of a status-responsedata format (step S9).

The status-response data, in the form in which the job-administration IDinformation is added, is supplied to the data-transmissionadministration portion 10 so as to be stored temporarily in thetransmitting buffer or the like, followed by being returned to the hostcomputer 1 at the timing of the bidirectional interface (step S10).

The printer-language analyzing portion 4 receives a next command fromthe data-receipt administration portion 3 to analyze the contents of thecommand, followed by repeating the foregoing process.

Thus, when the host computer 1 issues a command for the status responseand receives a status response corresponding to the command therefrom,the host computer 1 is able to refer to information of the time, atwhich the command for the status response has been received, as theinformation of the returned status response. Therefore, even if thestatus responses are not returned out of the sequential order, or evenif a long time has undesirably taken to return the status response, thecorrespondence between the returned status response and the command forthe status response can easily be discriminated. Thus, the state of theprinter apparatus can reliably be detected by the host computer for eachjob.

Seventh Embodiment

A seventh embodiment of the present invention will now be described.

In this embodiment, the job-administration ID is not automaticallyassigned by the job administration portion 3, but a job-administrationID, supplied from the host computer 1 together with job data, and,assigned by the host computer 1, is used to administrate jobs.

The flow of the process will now be described with reference to FIG. 23.

In the seventh embodiment, the host computer 1 communicates ajob-administration IDs for identifying the job to the printer apparatus2 together with a job start declaration (process 1) for the job (process2).

The job-administration ID is not different from that according to thefirst embodiment, but is determined by the host computer 1.

When the job administration portion 5 receives the job start declarationand the job-administration ID assigned to the job, the jobadministration portion 5 administrates the job-administration ID whilemaking this correspond to job data which will be supplied (process 3).

The job administration portion 5 does not assigns the job-administrationID. Other process is the same as that according to the sixth embodiment.

That is, the job-administration ID information added to the statusresponse is not assigned by the printer apparatus 2, but is specified bythe host computer 1.

FIG. 24 is a flow chart of the operation of the seventh embodiment.

The printer-language analyzing portion 4 receives data from thedata-receipt administration portion 3 (step S1).

Then, the process to be performed in accordance with this command isdiscriminated (step S2).

If the command orders any job control, this command is communicated tothe job administration portion 5 so that a corresponding jobadministration process is performed. Then, a discrimination is performedwhether or not the command orders to specify a job-administration ID(step S3).

If the command orders to specify a job-administration ID, adiscrimination is made that the specified administration ID is ajob-administration ID for the job so that the foregoing job isadministrated with this administration ID (step S4).

If the command does not order to specify a job-administration ID, acorresponding job administration process is performed (step S5).

If the command orders to perform any image-forming control, this commandis communicated to the image-forming and output portion 6 so that acorresponding process for forming and developing characters or graphicsor images is performed, and the developed image is printed out. If thecommand orders to control the printer apparatus 2, this command iscommunicated to the printer-apparatus control portion 7 so that theprinter control operation is performed (step S6).

If the command orders any status response, this command is communicatedto the status-response processing portion 8. The status-responseprocessing portion 8 investigates the corresponding state of theenvironment of the printer apparatus 2 (step S7).

The foregoing investigation cannot immediately be performed sometimesbecause a large quantity of information must be searched or the state ofthe printer apparatus 2 has been changed or due to the timing of theoperation. In the foregoing case, all processes are not interrupted, butthe employed multitask method enables the foregoing investigation to beperformed simultaneously with performing the other data process. Then,completion of the investigation is waited for.

After the investigation has been completed, its result is converted intostatus response data format information in the form of a characterstring or the like.

At this time, the printer apparatus 2 according to the present inventionadds, to the investigation information, job-administration IDinformation of the job requiring the response, so as to process responsedata in the form of a character string or the like of a status-responsedata format (step S8).

The status-response data, in the form in which the job-administration IDinformation is added, is supplied to the data-transmissionadministration portion 10 so as to be stored temporarily in thetransmitting buffer or the like, followed by being returned to the hostcomputer 1 at the timing of the bidirectional interface (step S9).

The printer-language analyzing portion 4 receives a next command fromthe data-receipt administration portion 3 to analyze the contents of thecommand, followed by repeating the foregoing process.

Thus, when the host computer 1, in a printing job, issues a command forthe status response and receives a status response corresponding to thecommand therefrom, the host computer 1 previously storingjob-administration IDs assigned to printing jobs by the host computer 1is able to refer to the job-administration ID of the job, the statusresponse of which has been required.

Therefore, even if the status responses are not returned out of thesequential order, or even if a long time has undesirably taken to returnthe status response, the correspondence between the returned statusresponse and the command for the status response can easily bediscriminated. Thus, the state of the printer apparatus can reliably bedetected by the host computer for each job.

As described above, when the host computer 1 issues a command for thestatus response and receives a status response corresponding to thecommand therefrom, the host computer 1 is able to refer to informationof the time, at which the command for the status response has beenreceived, as the information of the returned status response. Therefore,even if the status responses are not returned out of the sequentialorder, or even if a long time has undesirably taken to return the statusresponse, the correspondence between the returned status response andthe command for the status response can easily be discriminated. Thus,the state of the printer apparatus can reliably be detected by the hostcomputer.

As described above, the sixth and seventh embodiments have animprovement in which a job-administration ID, for identifying the job,is assigned to each job; and in which when a status response is returnedin such a manner that information of the job-administration ID is addedto the status response (see FIG. 36).

In an example case where a status response is returned when discharge ofa page has been completed, job-administration ID is added toconventional page discharge information, for example, “STATUS JOB-ID:37PAGE:3 FINISHED”.

As a result, even if a next Job is being processed when, for example, athird page has been discharged, and a corresponding status response hasbeen supplied to the host computer 1, reference to thejob-administration ID enables a discrimination to be performed that the“discharge of the third page” is the discharge of the “third page” ofthe “Job 1”.

When the host computer 1 has received a status response in which ajob-administration ID is added, the host computer 1 performs thefollowing process. FIG. 37 is a flow chart of the process to beperformed in the foregoing case.

Initially, the added job-administration ID information is read frominformation of the status response (step S1).

A checking is performed as to whether or not the addedjob-administration ID coincides with the job-administration ID of thejob, which is being processed by the host computer 1 (step S2).

If they coincide with each other, a discrimination is made that theinformation returned in the status response relates to the job, which isbeing performed, and this information is used (step S3).

If they do not coincide with each other, a discrimination is made thatthe status response is a status response for another job and the statusresponse does not relate to the job, which is being performed by thehost computer 1, and this status response is ignored (step S4).

Then, the operation proceeds to a process of a next status response.

As described above, a reference to a job-administration ID informationis performed; a discrimination is performed as to whether or not thestatus response relates to the job, which is being performed; and if thestatus response does not relate to the job, which is being performed,then it is ignored. Thus, the host computer is able to prevent anerroneous judgment because of receipt of information, which does notrelate to the present process. Furthermore, performing of wastefulprocess, that is performed due to non-required information, can beprevented.

If a colorant, such as toner or ink, for use in printing in aconventional printer apparatus is consumed in the printing operation toa degree that an image cannot be formed sufficiently, continuation ofthe printing operation causes the toner to run short. Thus, the formedimage blurs, and therefore a clear print cannot be produced.

Since a printed product becomes wasteful in the foregoing case, a statusresponse is sometimes transmitted to the host computer in order to issuea caution. For example, a status response, such as “STATUS TONER-LOW”,is returned to the host computer 1 (see process (5) of FIG. 36).

When the host computer 1 has received the foregoing status response, theprinting operation is temporarily stopped to prevent following printingoperation from being useless, and a message for supplying toner isdisplayed on the screen of the computer or the like to cope with thisstate.

In the sixth and seventh embodiments, the job-administration ID is usedto discriminate whether or not the subject status response relates tothe present job. If the status response does not relate to the presentjob, the response is ignored to improve the process efficiency.

In the foregoing case of toner shortage, expression, such as “STATUSJOB-ID: 37 TONER-LOW”, is performed (see process (6) of FIG. 36).

The foregoing status response is discriminated to be a responsecorresponding to the job, whose job-administration ID is “37” so thatreference is performed in the process of the Job 1, but no reference isperformed in the processes of the Jobs 2 and 3.

The foregoing phenomenon, the toner shortage, is critical thatdeteriorates the result of the printing operation of the present job,which is being performed, and following printing operations.

Although information of this must therefore be communicated to otherjobs except the printing job, which is being performed, the informationhas been ignored.

Since discrimination of the job-administration ID information causes allstatus responses, that do not relate to the present job, to be ignored,even if important information affecting the ensuing printing job isincluded in the response, it is not sometimes transmitted.

Eighth and ninth embodiments, structured to prevent the foregoingproblem, will now be described.

Eighth Embodiment

FIG. 27 is a diagram showing an example of a status response accordingto an eighth embodiment.

An assumption is made here that a first job 1 has been sent from thehost computer 1 to the printer apparatus 2 (process 1).

The printer-language analyzing portion 4 analyzes the supplied job datain command units. If the printer-language analyzing portion 4 hasreceived a job start declaration, it transmits the job start declarationto the job administration portion 5.

The job administration portion starts job administration in accordancewith the transmitted job start declaration, and administrates each jobwhile adding job-administration ID information to the job (process 2).

The job-administration ID information for use in this process may beinformation sent from the host computer 1 together with the job startdeclaration, or may be information automatically assigned by the printerapparatus 2.

The job-administration ID information must be capable of identifying therespective jobs, and the same job-administration ID for the same jobmust be used between the printer apparatus and the host computerregardless of the form of the job-administration ID.

For example, administration is performed such that a job-administrationID assigned to the first Job 1 is “37”, that assigned to the second Job2 is “38” and that assigned to the third Job 3 is “39”.

Then, the host computer 1 requires status response of variousinformation of the printer apparatus 2 (process (3)).

The foregoing status responses are classified into status, such asinformation about the available paper size, that can be immediatelyreturned; status, such as the state of the printer, that changes alwaysand that must be returned whenever the change occurs; status, such asthe page discharge state, that must be responded while waiting forcompletion of the process by the printer engine.

Therefore, status responses are sometimes returned to the host computer1 after a long time has passed from the receipt of a command for thestatus response.

Therefore, a case will occur frequently where the first Job 1 has beencompleted in the host computer 1, and the next Job 2 has started.

Accordingly, the status-response processing portion 8 returns the statusresponse information to the host computer 1 while adding theadministration ID information assigned to each job to the statusresponse information (process (4)).

An assumption is made here that the third page has been printed outduring a process of output data in the Job 1. If a status of the pagedischarge has been required from the host computer 1, information aboutcompletion of the discharge of the third page must be communicated tothe host computer 1.

At this time, the status-response processing portion 8 adds, to the pagedischarge information, administration ID “37” of the Job 1 so that theinformation is expressed by a character string or the like, such as“STATUS JOB-ID: 37 PAGE:3 FINISHED”, and the information is transmittedto the host computer 1.

The host computer 1 subjects, to a comparison, the job administration IDadded to the conventional status response and the presentjob-administration ID, assigned to each job-administration ID. Thus, thehost computer 1 is able to discriminate easily the job data in which thereturned status response has been generated.

When the status response is issued, the status-response processingportion 8 discriminates whether or not the “page discharge information”is important information that must be communicated to jobs except theJob 1.

The page discharge information is used to notify the page of the job,which has been output, and is a meaning information for the subject job,but is not important for other jobs.

Therefore, the status-response processing portion 8 does not addinformation indicating importance to the foregoing status response.

As a result of the process performed by the status response processingportion 8, status response, such as “STATUS JOB-ID:37 PAGE:3 FINISHED”,is transmitted to host computer 1.

The host computer 1 is able to discriminate that the page dischargeinformation relates to the page discharge having job-administration ID“37” in accordance with information “STATUS JOB-ID:37 PAGE:3 FINISHED”.

Also a fact can be detected that the foregoing status response is aresponse peculiar to the job having the administration ID “37”.

As a result of the discrimination performed by the host computer 1, thejob-administration ID “37”, assigned to the Job 1 at the time of startof the Job 1, and the ID, added to the status response, coincide witheach other. Therefore, the status response is a status responsegenerated due to data in Job 1.

Furthermore, the status response does not coincide with thejob-administration ID “38” of the Job 2, which is being performed by thehost computer 1. Therefore, a fact can be detected that the statusresponse is a peculiar response for another job.

Therefore, the foregoing status response does not relate to the Job 2,and whose contents are not required to be analyzed, and correspondingprocess is not required to be performed. Thus, the foregoing statusresponse is ignored.

An assumption is made here that any problem, such as toner shortage,takes place during output of the third page.

If toner shortage takes place, an image of satisfactory quality cannotbe formed and the produced output print becomes wasteful.

In order to quickly overcome the foregoing problem, the printerapparatus 2 transmits a status response of a caution of toner shortageto the host computer 1 (process 5).

When the foregoing status response is issued, the status-responseprocessing portion 8 according to the present invention discriminateswhether or not “toner-shortage caution information” is an importantinformation that must be communicated to other jobs as well the Job 1.

The toner shortage caution is an important status response that alsorelates to forming of images in other jobs to be processed later.

Therefore, the status-response processing portion 8 adds informationindicating importance to the foregoing status response.

For example, the status-response processing portion 8 adds, for example,a character string “*CAUTION*”.

As a result of the process performed by the status-response processingportion 8, a status response, such as “STATUS *CAUTION* JOB-ID:37TONER-LOW”, is transmitted to the host computer 1.

The host computer 1 is able to recognize that the toner shortage hastaken place during the job having the job administration ID “37” and itis an important information also relating to other jobs in accordancewith the sent status response.

As a result of the discrimination performed by the host computer 1, theforegoing status response is analyzed in all jobs, which are beingperformed by the host computer 1, and required coping operations areperformed.

Since information indicating the status response is an important statusresponse is added so as to be discriminated, information relating to alljobs is not ignored but can be transmitted.

FIG. 28 is a flow chart of the operation according to the presentinvention in which the printer-language analyzing portion 4 processesdata in command units to perform job processing processes, image formingprocesses, control processes and status-response processes.

The printer-language analyzing portion 4 receives data from thedata-receipt administration portion 3 (step S1).

Then, the process to be performed in accordance with the issued commandis discriminated (step S2).

If the command instructs any job control operation, this command istransmitted to the job administration portion 5 so that a correspondingjob control process is performed.

The job administration portion 5 administrates jobs in such a mannerthat job-administration IDs are assigned to respective printing jobs(step S3).

If any image forming control is instructed, this command is transmittedto the image-forming and output portion 6 so that processes for formingand developing images, such as characters, graphics and images areperformed, and the images are printed out. If any printer-controloperation is instructed, this command is transmitted to theprinter-apparatus control portion 7 so that a corresponding printercontrol operation is performed (step S4).

If the command orders any status response, this command is transmittedto the status-response processing portion 8. The status-responseprocessing portion 8 investigates a corresponding environment of theprinter apparatus 2 (step S5).

The foregoing investigation cannot immediately be performed sometimesbecause a large quantity of information must be searched or the state ofthe printer apparatus 2 has been changed or due to the timing of theoperation. In the foregoing case, all processes are not interrupted, butthe employed multitask method enables the foregoing investigation to beperformed simultaneously with performing the other data process. Then,completion of the investigation is waited for.

After the investigation has been completed, a result of it is convertedinto status response data format information, such as a characterstring.

The status-response processing portion 8 adds information of thejob-administration ID of the job, which has required the foregoingresponse, to information of the result of the investigation so as toprocess response data in the form of a character string or the likehaving a status-response data format (step S6).

Then, the status-response processing portion 8 discriminates whether theforegoing status response is not peculiar to the subject job, but is animportant response relating to all jobs (step S7).

If the status response is an important response relating to all jobs,the status-response processing portion 8 adds information indicatingimportance to the foregoing status response (step S8).

The information is expressed by using, for example, a character string“*CAUTION*” according to the foregoing embodiment.

The status response data in the form, in which the job-administration IDinformation and information indicating importance are added, istransmitted to the data-transmission administration portion 10, followedby being temporarily stored in a transmitting buffer or the like. Then,the status response data is returned to the host computer 1 at thetiming of the bidirectional interface (step S9).

The printer-language analyzing portion 4 receives a next command fromthe data-receipt administration portion 3 to analyze the command andrepeat the foregoing process.

FIG. 29 is a flow chart showing the process to be performed by the hostcomputer 1 according to the present invention.

When a status response is received from the printer apparatus 2, adiscrimination is performed whether or not information indicatingimportance is added (step S1).

If information indicating importance is added, a discrimination isperformed that the status response is an important information relatingto all jobs, and the contents of the status response are analyzed,followed by performing corresponding processes (step S2).

If information indicating importance is not added, a discrimination isperformed that the foregoing status response is information peculiar toa job.

Then, job-administration ID information added to the status response isread from information of the status response (step S3).

Then, a discrimination is performed as to whether or not the readjob-administration ID coincides with the job-administration ID of thejob which is being performed by the host computer 1 (step S4).

If they coincide with each other, a discrimination is performed thatinformation returned as the foregoing status response relates to thejob, which is being performed. Thus, the contents of the status responseare analyzed and corresponding process is performed (step S2).

If they do not coincide with each other, a discrimination is performedthat the foregoing status response is a status response for another joband it does not relate to the job, which is being performed by the hostcomputer 1. Thus, the foregoing status response is ignored (step S5).

Then, the following status response process is performed.

Thus, references to job-administration ID information and informationindicating importance are performed to discriminate whether or not theresponse relates to the job, which is being performed; if it relates thejob, which is being performed, then the foregoing information is used;if it does not relate to the job, it is ignored. Therefore, the hostcomputer is able to easily receive only required information to performthe printing process while appropriately recognizing the state of theprinter apparatus.

As a result, when the host computer 1, in a printing job, issues acommand for the status response and receives a status responsecorresponding to the command therefrom, the host computer 1 is able torecognize job-administration ID previously assigned to the printing joband stored in the printer apparatus; is able to refer to thejob-administration ID information of the job, which has demanded aresponse, as information of the returned status response; and is able torefer to information indicating that the response is an important statusresponse relating to all jobs. Therefore, even if a long time hasundesirably passed to return of the status response, and timing delaytakes place from the job process performed by the host computer, thecorrespondence between the returned status response and the command forthe status response in the job can easily be discriminated.

Furthermore, a discrimination can easily be performed as to whether ornot the subject status response is an important status response relatingto all jobs. Therefore, the state of the printer apparatus can reliablybe recognized by the host computer.

Ninth Embodiment

A ninth embodiment of the present invention will now be described withreference to the drawings.

In this embodiment, in a case where the subject status response does notrelate to all jobs, but is peculiar to each job, information indicating,that the status response is peculiar to each job, is added to the statusresponse, followed by transmitting the status response to the hostcomputer 1.

The flow of the process will now be described with reference to FIG. 30.

The status-response processing portion 8 checks the contents of a statusresponse, which is intended to be returned, to perform a discriminationas to whether or not the subject response is peculiar to each job.

For example, a status response indicating the page discharge state ineach job is information peculiar to each job, and is not important forother jobs.

Therefore, the status-response processing portion 8 adds information,indicating that the status response is peculiar to each job, to thestatus response.

For example, a character string “*LOCAL*” is added to express theinformation by a character string “STATUS *LOCAL* JOB-ID:37 PAGE:3FINISHED”, followed by transmitting the information to the host computer1 (process S4).

For example, a status response, such as “toner shortage cautioninformation” is important information relating to all jobs.

In the foregoing case, information indicating that the status responseis peculiar to each job is not added.

For example, a status response, such as “STATUS JOB-ID:37 TONER-LOW”, istransmitted to the host computer 1.

FIG. 31 is a flow chart showing the operation of a printer apparatusaccording to the ninth embodiment.

Since steps (1) to (6) are the same as those according to the firstembodiment, they are omitted from description.

The status-response processing portion 8 discriminates whether or notthe subject status response is peculiar to each job (step S7).

If the status response is peculiar to each job, information indicatingthe response is peculiar to each job to the job is added to the statusresponse data (step S8).

The information is, for example, a character string “*LOCAL*” asdescribed in the foregoing embodiment.

The status response data in the form, in which the job-administration IDinformation and information indicating that the status response ispeculiar to each job are added, is transmitted to the data-transmissionadministration portion 10, followed by being temporarily stored in atransmitting buffer or the like. Then, the status response data isreturned to the host computer 1 at the timing of the bidirectionalinterface (step S9).

The printer-language analyzing portion 4 receives a next command fromthe data-receipt administration portion 3, analyzes the contents of thesupplied command, and repeats the foregoing process.

FIG. 32 is a flow chart showing the operation to be performed by thehost computer 1 according to the present invention.

When the host computer 1 receives the status response, the host computer1 checks whether or not information indicating that the subject statusresponse is peculiar to each job is added to the status response (stepS1).

If information indicating that the subject status response is peculiarto each job is added, job-administration ID information is examined(step S2).

If the job-administration ID information coincides with thejob-administration ID of the job, which is being performed by the hostcomputer 1, then the contents of the status response are analyzed toperform a corresponding process (step S3). If they do not coincide witheach other, the foregoing status response is ignored (step S4).

If information indicating that the subject status response is peculiarto each job is not added, a discrimination is performed that the subjectstatus response is important information relating to all jobs, and thecontents of the status response are analyzed so that a correspondingprocess is performed (step S5).

As described above, information indicating that the subject statusresponse is peculiar to each job is added, and it is discriminated sothat status responses, which do not relate to the subject statusresponse, are skipped in reading. Thus, the process efficiency can beimproved while performing reference to important information relating toall jobs.

Tenth Embodiment

A tenth embodiment of the present invention will now be described withreference to the drawings.

In this embodiment, if the subject status response is an importantresponse relating to all jobs, information indicating importance isadded. If the subject status response is peculiar to each job,information indicating that the subject status response is peculiar toeach job is added, followed by transmitting the status response to thehost computer 1.

The flow of the process will now be described with reference to FIG. 33.

The status-response processing portion 8 checks the contents of thestatus response intended to be returned to discriminate that theresponse is an important response relating to all jobs or is peculiar toeach job.

For example, the status response, indicating the page discharge state ineach job, is information peculiar to each job, but is not important forother jobs.

Accordingly, the status-response processing portion 8 adds, to theforegoing status response, information indicating that the subjectstatus response is peculiar to each job.

For example, a character string, such as “*LOCAL*”, is added to expressthe information by a character string, such as “STATUS *LOCAL* JOB-ID:37PAGE:3 FINISHED”, followed by transmitting the information to the hostcomputer 1 (process S4).

For example, a status response, such as “toner shortage cautioninformation” is important information relating to all jobs.

Therefore, the status-response processing portion 8 adds, to theforegoing status response, information indicating that the subjectstatus response is an important response relating to all jobs.

For example, a status response, such as “STATUS *CAUTION* JOB-ID:37TONER-LOW”, formed by adding a character string, such as “*CAUTION*”, istransmitted to the host computer 1.

FIG. 34 is a flow chart of the operation of the printer apparatusaccording to this embodiment.

Since steps (1) to (6) are the same as those according to the eighthembodiment, they are omitted from illustration.

The status-response processing portion 8 discriminates that the subjectstatus response is an important response relating to all jobs or thesame is peculiar to each job (step S7).

If the subject status response is an important response relating to alljobs, information, indicating that the status response is an importantresponse relating to all jobs, is added to the foregoing status response(step S8).

The foregoing information is a character string, for example“*CAUTION*”, as described in the foregoing embodiment.

If the subject status response is peculiar to each job, informationindicating that the subject status response is peculiar to each job isadded to the status response data (step S9).

Status response data, in the form in which the job-administration IDinformation and information indicating the subject status response is animportant response relating to all jobs or information indicating thatthe subject status response is peculiar to each job, is transmitted tothe data-transmission administration portion 10. Then, the statusresponse data is temporarily stored in a transmitting buffer or thelike, followed by being returned to the host computer 1 at the timingdetermined by the bidirectional interface (step S10).

The printer-language analyzing portion 4 receives a next command fromthe data-receipt administration portion 3, analyzes the contents of thesame, and repeats the foregoing process.

FIG. 35 is a flow chart showing the process to be performed by the hostcomputer 1 according to the present invention.

When the host computer 1 receives the status response, the host computerchecks that the information relating to all jobs or informationindicating that the subject status response is peculiar to each job isadded (step S1).

If the status response is peculiar to each job, its job-administrationID information is examined (step S2).

If the job-administration ID information coincides with thejob-administration ID of the job, which is being performed, the contentsof the status response is analyzed so that a corresponding processing isperformed (step S3). If they do not coincide with each other, theforegoing status response is ignored (step S4).

If the subject status response relates to all jobs, its contents areanalyzed regardless of whether or not the difference from theadministration ID of the job, which is being performed by the hostcomputer 1 so that a corresponding process is performed (step S5).

As described above, information indicating that the subject statusresponse relates to all jobs, or information indicating that the subjectstatus response is peculiar to each job, is added so as to bediscriminated. Thus, the status responses, that do not relate to thesubject job, are skipped in reading. As a result, the process efficiencycan be improved, and reference can be made to important informationrelating to all jobs.

As described above, according to the eighth and ninth embodiments, whenthe host computer has issued, in a printing job, a command for thestatus response and has received a corresponding status response, thehost computer is able to recognize the job-administration ID assigned tothe printing job and stored in the printer apparatus; the host computeris able to refer to the job-administration ID information of the job,which has required the response, as information of the returned statusresponse; and reference can be made to information indicating that thesubject status response is an important status response relating to alljobs or information indicating that the subject status response ispeculiar to each job. Therefore, even if a long time has undesirablytaken to return the status response and therefore timing delays fromthat of the job, which is being performed by the host computer, thecorrespondence between the status response and the return of the commandfor the status response of the job can easily be discriminated.Furthermore, a discrimination can easily be performed that the subjectstatus response is an important status response relating to all jobs orthe same is a status response that may be skipped in reading because itis peculiar to each job. Therefore, the state of the printer apparatuscan reliably be recognized by the host computer.

Eleventh Embodiment

An eleventh embodiment of the present invention will now be describedwith reference to the drawings.

FIG. 38 is a block diagram showing the structure of a printer apparatusaccording to eleventh, twelfth and thirteenth embodiment.

In this embodiment, the description will be made about a page printer.

Referring to FIG. 1, reference numeral 1 represents a host computer,which generates output data, such as characters and graphics, and avariety of control commands, and which generates a command for thestatus response for recognizing a variety of information items of theprinter apparatus, in order to input the foregoing data and commands toa printer apparatus 2 which is the main portion of an output apparatus.

The host computer 1 and the printer apparatus 2 are connected to eachother through a bidirectional interface so that data can be transferredfrom the host computer 1 to the printer apparatus 2, and data can bereturned from the printer apparatus 2 to the host computer 1.

In the printer apparatus 2, reference numeral 3 represents adata-receipt administration portion that receives data, such ascharacters and graphics, the various control commands and the commandfor the status response, which are supplied from the host computer 1, soas to administrate the data and commands.

The data-receipt administration portion 3 has a receiving buffer forreceiving and temporarily storing data from the host computer 1.

Reference numeral 4 represents a printer-language analyzing portion thatanalyzes the detailed contents of a command, and that instructs thecorresponding control in accordance with the contents of the command.

The printer-language analyzing portion 4 sequentially receives thecommands stored in the data-receipt administration portion 3, andinvestigates the contents of the commands in accordance with thedescription rule of the printer language so as to discriminate whatprocess is demanded to be performed.

If a result of the discrimination indicates that the command is acommand relating to a job administration, such as start or completiondeclaration of a printing job, a corresponding job administrationcommand is issued to a job administration portion 5.

If the command orders to form an image, such as characters, graphics orimages, a command for forming a corresponding image is issued to theimage-forming and output portion 6.

If the command orders to control the printer apparatus 2, a command isissued to the printer-apparatus control portion 7 to perform acorresponding control. If the command requires any status response, acommand is issued to the status-response processing portion 8 to performa corresponding status response.

Reference numeral 5 represents a job administration portion.

The job administration portion 5 processes printing data supplied fromthe host computer 1 in accordance with job administration command fromthe printer-language analyzing portion 4.

Reference numeral 6 represents an image-forming and output portion forforming and developing images, such as characters, graphics or images tobe output.

The image-forming and output portion 6 forms a corresponding characterpattern, calculates a graphic or forms an image and develops image datain accordance with a command for forming and outputting an image fromthe printer-language analyzing portion 4, followed by transmittingdeveloped data to be output to a printer engine 9.

The printer engine 9 is an apparatus, such as a laser beam printerengine, that uses a procedure of an electrophotographic method or thelike to perform a printing out process in accordance with the developedimage received from the image-forming and output portion 6.

Reference numeral 7 represents the printer-apparatus control portionthat controls and administrates the printer apparatus 2, such that itselects paper to be used and initializes the printer apparatus 2, inaccordance with the printer-apparatus control command from theprinter-language analyzing portion 4.

Reference numeral 8 represents a status-response processing portion thatinvestigates the corresponding environment of the printer apparatus 2 inaccordance with the command for the status response from theprinter-language analyzing portion 4. In accordance with the contents ofthe result, the status-response processing portion 8 processes statusresponse information expressing the contents by means of a format, suchas a character string, to transmit the status response information tothe data-transmission administration portion 10.

When the data data-transmission administration portion 10 receives thestatus response information returned from the status-response processingportion 8, the data-transmission administration portion 10 temporarilystores it in the transmitting buffer or the like, followed by returningit to the host computer 1 at the timing determined by the bidirectionalinterface.

The job administration portion 5 according to the present inventionsupervises the data-receipt administration portion 3 to check the statewhere job data, which is being processed, is transmitted from the hostcomputer 1.

If the job data interrupts, time taken from this moment is measured.

The time is measured by referring to time information obtained by atimer administration portion 11 or the like.

The job administration portion 5 checks whether or not the time takenfrom the job data interruption is longer than a predetermined time.

The predetermined time has been previously set in accordance with acommand issued by the host computer 1, or is set by operating the panelof the printer apparatus 2, or is automatically calculated in theprinter apparatus 2, or a fixed value has been initially set.

If the predetermined time has passed from the interruption of the jobdata, the job administration portion 5 discriminates that “the subjectjob has been completed while neglecting a correct job procedure due tosome reason”.

In order to omit the interrupted job, a job time-out process isperformed and preparations for a forcible job completion process and anext job process are performed.

Simultaneously, the job administration portion 5 according to thepresent invention instructs the status-response processing portion 8 toissue a status response in order to communicate generation of job timeout.

As a result, a character string, such as “STATUS JOB-ID:37 JOB-TIMEOUT”,is status-responded to the host computer 1.

When the host computer 1 receives the character string or the like, thehost computer 1 recognizes that the job having the administration ID“37”, is time out.

If the host computer 1 continues the foregoing job, the job isinterrupted in accordance with the time out in the printer apparatus 2.

As an alternative to this, prior to transmitting following job data tothe printer apparatus 2, a procedure is issued, such as a declarationfor starting a new job, resetting of a printer environment orre-registration of a font to be used.

Thus, if job time out has taken place in the printer apparatus 2, alsothe host computer 1 is able to recognize this. Therefore, erroneoustransmission of the interrupted job causing inadequate document outputand disorder of following jobs can be prevented.

FIG. 39 is a flow chart showing the operation of the present invention,in which the job administration portion 5 supervises job data so thatany process is performed.

The job administration portion 5 supervises a state where job data isreceived by the data-receipt administration portion 3 (step S1).

The job administration portion 5 checks whether or not job data is beingtransmitted from the host computer 1 (step S2).

If job data has been transmitted, it is sent to the printer-languageanalyzing portion 4, and a process for forming and outputting an image,a printer control process, a status response process or a jobadministration process are performed in accordance with the describedcontents (step S3).

If no data is transmitted but the job is interrupted, reference to timeinformation of the timer administration portion 11 is performed tomeasure time passed from start of the job data interruption (step S4).

Then, checking is performed as to whether or not time has been passed bya predetermined time (step S5). The foregoing predetermined time isregulated time serving as a reference for time out discrimination. Thepredetermined time has been previously set in accordance with a commandissued by the host computer 1, or is set by operating the panel of theprinter apparatus 2, or is automatically calculated in the printerapparatus 2, or a fixed value has been initially set.

If the time taken from start of interruption of the job data is notlonger than the foregoing predetermined time, a discrimination isperformed that performing the job time-out put process is too early tobe performed, and supervisory of the state, where the job data isreceived, is again performed (step S1).

If the time taken from it is longer than the predetermined time, adiscrimination is performed whether or not a job is being performed(step S6).

The job control is performed when a job control command, such as a jobstart declaration or a job completion declaration is sent from the hostcomputer 1. The job administration portion 5, which has been instructedby the printer-language analyzing portion 4 as a result of the commandanalysis, performs execution of the job.

An assumption is performed that the predetermined time has passed frominterruption of job data and, as well the job has been completed at thetime of the job time out.

Another assumption is performed that the job data is processed inaccordance with a formal job description format and all job data itemshave been received from the host computer 1. The foregoing case is ausual job process.

If new job data has not been supplied at this time, there is apossibility that the data-receipt administration portion 3 is brought tostate where it waits for data receipt and the predetermined time passesas a result of checking of the time in which data receipt is waited for.

However, in the foregoing case, the job immediately before has beencompleted in the formal procedure, and the present state is not a jobexecution state. Therefore, following job processes are not affectedadversely.

Since the necessity of forcibly ending the job by the job time outprocess can be eliminated as described above if the job is not beingperformed, supervisory of the state where job data is received is againperformed (step S1).

If a job is being performed, the present job must be excluded to arrangethe environment of the printer in order to perform a following job-dataprocess as described above.

Accordingly, as the job time out process, the present job is forciblyended and the environment is arranged for a job which will be sent next(step S7).

As a result of the job completion process, the page, which is beingsubjected to an image forming process and therefore left in the printerapparatus 2, is discharged as it is or the operation is omitted.Furthermore, a font download from the host computer 1 is deleted or aprinter environment set to perform the job is reset.

Then, the job administration portion 5 according to the presentinvention issues a status response indicating generation of job time outto the host computer 1 in synchronization with the forcible jobcompletion process due to the job time out (step S8).

When the host computer 1 receives the status response indicating thegeneration of job time out, the host computer 1 recognizes that the jobcompletion process has been forcibly performed in the printer apparatus2. Thus, the host computer 1 stops the corresponding job to be performedtherein or again issues data, such as job start declaration to transmitfollowing data.

As described above, reference to the status response indicatinggeneration of job time out is performed; and the job process in the hostcomputer 1 is changed in synchronization with the forcible ending of thejob in the printer apparatus, so that the linkage between the hostcomputer and the printer apparatus is improved so that a job problem ina printing job can be prevented.

Since a job problem can be prevented, the necessity of paying attentionto the state where the printer is performing an operation and the statewhere the host computer is performing an operation can be eliminated,and therefore the job time out can be performed relatively easily.

That is, if job data is interrupted, next data receipt is not, as hasbeen done with the conventional structure, waited for carefully for along time, but the job time out process can be performed safely in ashort time. Thus, in a printing system that must process a plurality ofjobs in a large quantity, an efficient job operation can be performed.

Note that the order of the checking whether or not time is longer thanthe predetermined time in step (5) and the checking whether or not a jobis being performed in step (6) may be made contrary.

Since it is usually easy to check whether or not a job is beingperformed, the processing efficiency can be sometimes improved in a casewhere step (6) is performed first.

Twelfth Embodiment

A twelfth embodiment of the present invention will now be described withreference to the drawings.

In the twelfth embodiment, if time taken from job data interruption islonger than a predetermined time, the job time out process is notimmediately performed, but a status response indicating generation ofthe job time out is alarmed to the host computer 1.

In response to the job time out alarm, the host computer 1 issues aninstruction whether or not job time out may be performed, and followingoperations are performed in accordance with the foregoing instruction.

The operation of this embodiment will now be described with reference toa flow chart shown in FIG. 40.

Since steps (1) to (6) are the same as those according to the eleventhembodiment, they are omitted from the description.

If time taken from the job data interruption is longer than apredetermined time and, as well a job is being performed, the presentjob process must be abandoned and the operation proceeds to a next jobprocess to maintain the printing efficiency.

Accordingly, the job time out process is performed. However, theforegoing passing over the predetermined time may be due to a fact thatthe data processing process in the host computer 1 takes a long time,and therefore data cannot be transmitted as desired.

If the printer apparatus 2 ends the job therein though the host computer1 has the intention to continue the job, there is a possibility that allensuing job processes are spoiled as described above.

Accordingly, the job administration portion 5 according to the presentinvention issues, to the host computer 1, an alarm that job time out hastaken place and the present job is forcibly ended by means of a statusresponse, the alarm being issued prior to perform the job time outprocess.

Then, issue of an instruction from the host computer 1 whether or notthe job time out may be performed is waited for (step S7).

The status response of the job time out alarm to be issued at this timeis in the form of a character string, such as “STATUS JOB-ID:37JOB-TIMEOUT OK?”.

When the host computer 1 has received the foregoing status response, thehost computer 1 discriminates whether or not the foregoing job will becontinued. If the job will be continued, “job time out inhibitioncommand” is issued to the printer apparatus 2. If there is no intentionto continue the job, “job time out permission command” is issued to thesame.

The printer apparatus 2 analyzes the command relating to the job timeout to discriminate whether or not the foregoing command permits the jobtime out (step S8).

If the job time out is not permitted, the printer apparatus 2discriminates that the host computer 1 has an intention to continue thejob, and waits for supply of following job data (step S1).

If the job time out is permitted, the printer apparatus 2 discriminatesthat the host computer 1 has abandoned continuation of the subject job,and the printer apparatus 2 performs a forcible completion process ofthis job as a job time out process (step S9).

Then, the foregoing job process is abandoned, and the operation proceedsto a next job process.

As described above, a status response alarming generation of job timeout is received from the printer apparatus prior to performing the jobtime out process; and the host computer 1 issues a command whether ornot the job time out process may be performed. Thus, the job is notended by the printer apparatus, but it can be ended after inquiry of theconvenience. As a result, the linkage between the host computer and theprinter apparatus is improved so that a job problem in a printing jobcan be prevented.

Since a job problem can be prevented, the necessity of paying attentionto the state where the printer is performing an operation and the statewhere the host computer is performing an operation can be eliminated,and therefore the job time out can be performed relatively easily.

That is, if job data is interrupted, next data receipt is, as has beendone with the conventional structure, waited for carefully for a longtime, but the job time out process can be performed safely in a shorttime. Thus, in a printing system that must process a plurality of jobsin a large quantity, an efficient job operation can be performed.

Thirteenth Embodiment

A thirteenth embodiment of the present invention will now be describedwith reference to the drawings.

In this embodiment, if time from job data interruption is longer than apredetermined time, the job time out process is not immediatelyperformed, but generation of job time out is alarmed to the hostcomputer 1 by means of a status response.

If no response, for example, following job data, is performed from thehost computer 1 though the job time out alarm has been issued, adiscrimination is performed that the host computer 1 has no intention tocontinue the job, and the job time out process is performed.

The operation of this embodiment will now be described with reference toa flow chart shown in FIG. 41.

Since steps (1) to (6) are the same as those of the eleventh embodiment,they are omitted from the description.

If time taken from the job data interruption is longer than apredetermined time and, as well a job is being performed, the presentjob process must be abandoned and the operation proceeds to a next jobprocess to maintain the printing efficiency.

Accordingly, a job time out process is performed. However, the foregoingpassing over the predetermined time may be due to a fact that the dataprocessing process in the host computer 1 takes a long time, andtherefore data cannot be transmitted as desired.

If the printer apparatus 2 ends the job therein though the host computer1 has the intention to continue the job, there is a possibility that allensuing job processes are spoiled as described above.

Accordingly, the job administration portion 5 according to the presentinvention issues, to the host computer 1, an alarm that job time out hastaken place and the present job is forcibly ended by means of a statusresponse, the alarm being issued prior to perform the job time outprocess.

Then, issue of a response, such as following job data, from the hostcomputer 1 is waited for (step S7).

The status response of the job time out alarm to be issued at this timeis in the form of a character string, such as “STATUS JOB-ID:37JOB-TIMEOUT OK?”.

When the host computer 1 has received the foregoing status response, thehost computer 1 discriminates whether or not the foregoing job will becontinued. If the job will be continued, following job data is issued,or, in a case where following job data cannot be supplied immediately,information indicating an intention of continuation of the job isissued.

If there is no intention to continue the job, no data is issued.

The printer apparatus 2 discriminates whether or not any response hasbeen made from the host computer 1 to judge whether or not the job isintended to be continued (step S8).

That is, if following job data or any response indicating the intentionto continue the job has been sent from the host computer 1, adiscrimination is made that the job is intended to be continued, andreceived data is analyzed, followed by performing a correspondingprocess (step S3).

If no response has been made from the host computer 1, a discriminationis performed that the host computer 1 has abandoned continuation of theforegoing job and the printer apparatus 2 performs a forcible completionprocess of this job as a job time out process (step S9).

Then, the foregoing job process is abandoned, and the operation proceedsto a next job process.

Another difference from the twelfth embodiment is that the fact “noresponse has been made” is used in the thirteenth embodiment todiscriminate that the job is not intended to be continued.

In an example case where information cannot be transmitted/supplied toand from the host computer 1 due to disconnection of a communicationline for example, no response can be made from the host computer 1 if ajob time out alarm is issued.

The thirteenth embodiment is characterized in that the foregoing casecan be discriminated as “no intention to continue the job”.

As described above, a status response alarming generation of job timeout is received from the printer apparatus prior to performing the jobtime out process; and the host computer 1 transmits following job dataor information indicating the continuation intention. Thus, the job isnot ended by the printer apparatus, but it can be ended after inquiry ofthe convenience. As a result, the linkage between the host computer andthe printer apparatus is improved so that a job problem in a printingjob can be prevented.

Since a job problem can be prevented, the necessity of paying attentionto the state where the printer is performing an operation and the statewhere the host computer is performing an operation can be eliminated,and therefore the job time out can be performed relatively easily.

That is, if job data is interrupted, next data receipt is not, as hasbeen done with the conventional structure, waited for carefully for along time, but the job time out process can be performed safely in ashort time. Thus, in a printing system that must process a plurality ofjobs in a large quantity, an efficient job operation can be performed.

As described above, according to the eleventh, twelfth and thethirteenth embodiments, even if a job completion process is forciblyperformed due to a job time out process after a predetermined time haspassed, generation of the job time out can be, by means of a statusresponse, communicated from the printer apparatus to the host computer;and in accordance with the foregoing information, the host computer isable to continue or abandon or cope with the job process in such amanner that communication is established between the host computer andthe printer apparatus in a linkage manner. Thus, the linkage between thehost computer and the printer apparatus can be improved so that a jobproblem in a printing job can be prevented.

Since a job problem can be prevented, the necessity of paying attentionto the state where the printer is performing an operation and the statewhere the host computer is performing an operation can be eliminated,and therefore the job time out can be performed relatively easily.

That is, if job data is interrupted, next data receipt is not, as hasbeen done with the conventional structure, waited for carefully for along time, but the job time out process can be performed safely in ashort time. Thus, in a printing system that must process a plurality ofjobs in a large quantity, an efficient job operation can be performed.

Although the invention has been described in its preferred form with acertain degree of particularity, it is understood that the presentdisclosure of the preferred form can be changed in the details ofconstruction and the combination and arrangement of parts may beresorted to without departing from the spirit and the scope of theinvention as hereinafter claimed.

1-27. (canceled)
 28. An external apparatus that transmits a plurality ofprint jobs to a printing control apparatus via a bi-directioncommunication line, said external apparatus comprising: a generationunit that generates a job; a transmitter that transmits the plurality ofprint jobs generated by said generation unit; a first receiver thatreceives a job identifier which is assigned to each print job by saidprinting control apparatus, wherein each job identifier is unique andnot changed from generation until the print job is completed; a memorythat stores the job identifier received by said first receiver; a secondreceiver that receives progressing page information indicating how manypages have been finished before a process of the print job is completedfrom said printing control apparatus, together with the job identifierof the print job; and a specifying unit that specifies a particularjob's status including the progressing page information in accordancewith correspondence between the job identifier received by said secondreceiver together with the progressing page information and the jobidentifier stored in said memory.
 29. A printing control apparatus thatreceives a plurality of print jobs sent from an external apparatus via abi-direction communication line and processes the plurality of printjobs, the external apparatus executes a process related to a certainjob's status during processing the other job, said printing controlapparatus comprising: a storage device that stores the plurality ofprint jobs; an assigner that assigns a job identifier to each print jobstored in said storage device in response to receiving the print job,wherein each job identifier is unique and not changed from generationuntil the print job is completed; and a transmitter that transmits tothe external apparatus progressing page information indicating how manypages have been finished before the process of the print job iscompleted, together with the job identifier of the print job, whereinsaid transmitter transmits the progressing page information to make theexternal apparatus, which has the job identifier stored in a memory,specify the certain job's status, including the progressing pageinformation, in accordance with correspondence between the jobidentifier transmitted by said transmitter together with the progressingpage information and the job identifier stored in the memory.
 30. Aprinting control apparatus that receives a plurality of print jobs sentfrom an external apparatus via a bi-direction communication line andprocesses the plurality of print jobs, the external apparatus executes aprocess related to a certain job's status during processing the otherjob, stores a job identifier in a memory, specifies the certain job'sstatus including progressing page information in accordance withcorrespondence between a job identifier transmitted by said printingcontrol apparatus together with the progressing page information and thejob identifier stored in the memory, said printing control apparatuscomprising: a storage device that stores the plurality of print jobs; anassigner that assigns the job identifier to each print job stored insaid storage device in response to receiving the print job, wherein eachjob identifier is unique and not changed from generation until the printjob is completed; and a transmitter that transmits to the externalapparatus the progressing page information indicating how many pageshave been finished before process of the print job is completed,together with the job identifier of the print job.